diff --git a/cassandra/cqlengine/connection.py b/cassandra/cqlengine/connection.py
index 3d3cd89c..3070e67e 100644
--- a/cassandra/cqlengine/connection.py
+++ b/cassandra/cqlengine/connection.py
@@ -146,7 +146,7 @@ def unregister_connection(name):
     if name not in _connections:
         return
 
-    if _connections[name] == _connections[DEFAULT_CONNECTION]:
+    if DEFAULT_CONNECTION in _connections and _connections[name] == _connections[DEFAULT_CONNECTION]:
         del _connections[DEFAULT_CONNECTION]
         log.warning("Unregistering default connection '{0}'. Use set_default_connection to set a new one.".format(name))
 
diff --git a/cassandra/cqlengine/models.py b/cassandra/cqlengine/models.py
index 286d8c1f..1b198739 100644
--- a/cassandra/cqlengine/models.py
+++ b/cassandra/cqlengine/models.py
@@ -31,9 +31,12 @@ log = logging.getLogger(__name__)
 
 def _clone_model_class(model, attrs):
     new_type = type(model.__name__, (model,), attrs)
-    new_type.__abstract__ = model.__abstract__
-    new_type.__discriminator_value__ = model.__discriminator_value__
-    new_type.__default_ttl__ = model.__default_ttl__
+    try:
+        new_type.__abstract__ = model.__abstract__
+        new_type.__discriminator_value__ = model.__discriminator_value__
+        new_type.__default_ttl__ = model.__default_ttl__
+    except AttributeError:
+        pass
     return new_type
 
 
@@ -803,6 +806,8 @@ class BaseModel(object):
 
     def _inst_batch(self, batch):
         assert self._timeout is connection.NOT_SET, 'Setting both timeout and batch is not supported'
+        if self._connection:
+            raise CQLEngineException("Cannot specify a connection on model in batch mode.")
         self._batch = batch
         return self
 
diff --git a/cassandra/cqlengine/query.py b/cassandra/cqlengine/query.py
index 8b968c6f..f47b025f 100644
--- a/cassandra/cqlengine/query.py
+++ b/cassandra/cqlengine/query.py
@@ -302,18 +302,20 @@ class ContextQuery(object):
         self.models = []
 
         if len(args) < 1:
-            raise CQLEngineException("No model provided.")
+            raise ValueError("No model provided.")
 
         keyspace = kwargs.pop('keyspace', None)
         connection = kwargs.pop('connection', None)
 
         if kwargs:
-            raise CQLEngineException("Unknown keyword argument(s): {0}".format(
+            raise ValueError("Unknown keyword argument(s): {0}".format(
                 ','.join(kwargs.keys())))
 
         for model in args:
-            if not issubclass(model, models.Model):
-                raise CQLEngineException("Models must be derived from base Model.")
+            try:
+                issubclass(model, models.Model)
+            except TypeError:
+                raise ValueError("Models must be derived from base Model.")
 
             m = models._clone_model_class(model, {})
 
@@ -390,7 +392,8 @@ class AbstractQuerySet(object):
         if self._batch:
             return self._batch.add_query(statement)
         else:
-            result = _execute_statement(self.model, statement, self._consistency, self._timeout, connection=self._connection)
+            connection = self._connection if self._connection else self.model._get_connection()
+            result = _execute_statement(self.model, statement, self._consistency, self._timeout, connection=connection)
             if self._if_not_exists or self._if_exists or self._conditional:
                 check_applied(result)
             return result
diff --git a/tests/integration/cqlengine/test_connections.py b/tests/integration/cqlengine/test_connections.py
new file mode 100644
index 00000000..f2f88b0f
--- /dev/null
+++ b/tests/integration/cqlengine/test_connections.py
@@ -0,0 +1,389 @@
+# Copyright 2013-2016 DataStax, Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from cassandra import InvalidRequest
+from cassandra.cluster import NoHostAvailable
+from cassandra.cqlengine import columns, CQLEngineException
+from cassandra.cqlengine import connection as conn
+from cassandra.cqlengine.management import drop_keyspace, sync_table, drop_table, create_keyspace_simple
+from cassandra.cqlengine.models import Model
+from cassandra.cqlengine.query import ContextQuery, BatchQuery
+from tests.integration.cqlengine import setup_connection, DEFAULT_KEYSPACE
+from tests.integration.cqlengine.base import BaseCassEngTestCase
+
+
+class TestModel(Model):
+
+    __keyspace__ = 'ks1'
+
+    partition = columns.Integer(primary_key=True)
+    cluster = columns.Integer(primary_key=True)
+    count = columns.Integer()
+    text = columns.Text()
+
+
+class AnotherTestModel(Model):
+
+    __keyspace__ = 'ks1'
+
+    partition = columns.Integer(primary_key=True)
+    cluster = columns.Integer(primary_key=True)
+    count = columns.Integer()
+    text = columns.Text()
+
+
+class ContextQueryConnectionTests(BaseCassEngTestCase):
+
+    @classmethod
+    def setUpClass(cls):
+        super(ContextQueryConnectionTests, cls).setUpClass()
+        create_keyspace_simple('ks1', 1)
+
+        conn.unregister_connection('default')
+        conn.register_connection('fake_cluster', ['127.0.0.100'], lazy_connect=True, retry_connect=True, default=True)
+        conn.register_connection('cluster', ['127.0.0.1'])
+
+        with ContextQuery(TestModel, connection='cluster') as tm:
+            sync_table(tm)
+
+    @classmethod
+    def tearDownClass(cls):
+        super(ContextQueryConnectionTests, cls).tearDownClass()
+
+        with ContextQuery(TestModel, connection='cluster') as tm:
+            drop_table(tm)
+        drop_keyspace('ks1', connections=['cluster'])
+
+
+        # reset the default connection
+        conn.unregister_connection('fake_cluster')
+        conn.unregister_connection('cluster')
+        setup_connection(DEFAULT_KEYSPACE)
+
+
+    def setUp(self):
+        super(BaseCassEngTestCase, self).setUp()
+
+    def test_context_connection_priority(self):
+
+        # Set the default connection on the Model
+        TestModel.__connection__ = 'cluster'
+        with ContextQuery(TestModel) as tm:
+            tm.objects.create(partition=1, cluster=1)
+
+        # ContextQuery connection should have priority over default one
+        with ContextQuery(TestModel, connection='fake_cluster') as tm:
+            with self.assertRaises(NoHostAvailable):
+                tm.objects.create(partition=1, cluster=1)
+
+        # Explicit connection should have priority over ContextQuery one
+        with ContextQuery(TestModel, connection='fake_cluster') as tm:
+            tm.objects.using(connection='cluster').create(partition=1, cluster=1)
+
+        # Reset the default conn of the model
+        TestModel.__connection__ = None
+
+        # No model connection and an invalid default connection
+        with ContextQuery(TestModel) as tm:
+            with self.assertRaises(NoHostAvailable):
+                tm.objects.create(partition=1, cluster=1)
+
+    def test_context_connection_with_keyspace(self):
+
+        # ks2 doesn't exist
+        with ContextQuery(TestModel, connection='cluster', keyspace='ks2') as tm:
+            with self.assertRaises(InvalidRequest):
+                tm.objects.create(partition=1, cluster=1)
+
+
+class ManagementConnectionTests(BaseCassEngTestCase):
+
+    keyspaces = ['ks1', 'ks2']
+    conns = ['cluster']
+
+    @classmethod
+    def setUpClass(cls):
+        super(ManagementConnectionTests, cls).setUpClass()
+        conn.unregister_connection('default')
+        conn.register_connection('fake_cluster', ['127.0.0.100'], lazy_connect=True, retry_connect=True, default=True)
+        conn.register_connection('cluster', ['127.0.0.1'])
+
+
+    @classmethod
+    def tearDownClass(cls):
+        super(ManagementConnectionTests, cls).tearDownClass()
+
+        # reset the default connection
+        conn.unregister_connection('fake_cluster')
+        conn.unregister_connection('cluster')
+        setup_connection(DEFAULT_KEYSPACE)
+
+    def setUp(self):
+        super(BaseCassEngTestCase, self).setUp()
+
+    def test_create_drop_keyspace(self):
+
+        # No connection (default is fake)
+        with self.assertRaises(NoHostAvailable):
+            create_keyspace_simple(self.keyspaces[0], 1)
+
+        # Explicit connections
+        for ks in self.keyspaces:
+            create_keyspace_simple(ks, 1, connections=self.conns)
+
+        for ks in self.keyspaces:
+            drop_keyspace(ks, connections=self.conns)
+
+    def test_create_drop_table(self):
+
+        for ks in self.keyspaces:
+            create_keyspace_simple(ks, 1, connections=self.conns)
+
+        # No connection (default is fake)
+        with self.assertRaises(NoHostAvailable):
+            sync_table(TestModel)
+
+        # Explicit connections
+        sync_table(TestModel, connections=self.conns)
+
+        # Explicit drop
+        drop_table(TestModel, connections=self.conns)
+
+        # Model connection
+        TestModel.__connection__ = 'cluster'
+        sync_table(TestModel)
+        TestModel.__connection__ = None
+
+        # No connection (default is fake)
+        with self.assertRaises(NoHostAvailable):
+            drop_table(TestModel)
+
+        # Model connection
+        TestModel.__connection__ = 'cluster'
+        drop_table(TestModel)
+        TestModel.__connection__ = None
+
+        # Model connection
+        for ks in self.keyspaces:
+            drop_keyspace(ks, connections=self.conns)
+
+
+class BatchQueryConnectionTests(BaseCassEngTestCase):
+
+    conns = ['cluster']
+
+    @classmethod
+    def setUpClass(cls):
+        super(BatchQueryConnectionTests, cls).setUpClass()
+
+        create_keyspace_simple('ks1', 1)
+        sync_table(TestModel)
+        sync_table(AnotherTestModel)
+
+        conn.unregister_connection('default')
+        conn.register_connection('fake_cluster', ['127.0.0.100'], lazy_connect=True, retry_connect=True, default=True)
+        conn.register_connection('cluster', ['127.0.0.1'])
+
+
+    @classmethod
+    def tearDownClass(cls):
+        super(BatchQueryConnectionTests, cls).tearDownClass()
+
+        # reset the default connection
+        conn.unregister_connection('fake_cluster')
+        conn.unregister_connection('cluster')
+        setup_connection(DEFAULT_KEYSPACE)
+
+        drop_keyspace('ks1')
+
+    def setUp(self):
+        super(BaseCassEngTestCase, self).setUp()
+
+    def test_basic_batch_query(self):
+        """Test BatchQuery requests"""
+
+        # No connection with a QuerySet (default is a fake one)
+        with self.assertRaises(NoHostAvailable):
+            with BatchQuery() as b:
+                TestModel.objects.batch(b).create(partition=1, cluster=1)
+
+        # Explicit connection with a QuerySet
+        with BatchQuery(connection='cluster') as b:
+            TestModel.objects.batch(b).create(partition=1, cluster=1)
+
+        # Get an object from the BD
+        with ContextQuery(TestModel, connection='cluster') as tm:
+            obj = tm.objects.get(partition=1, cluster=1)
+            obj.__connection__ = None
+
+        # No connection with a model (default is a fake one)
+        with self.assertRaises(NoHostAvailable):
+            with BatchQuery() as b:
+                obj.count = 2
+                obj.batch(b).save()
+
+        # Explicit connection with a model
+        with BatchQuery(connection='cluster') as b:
+            obj.count = 2
+            obj.batch(b).save()
+
+    def test_batch_query_different_connection(self):
+        """Test BatchQuery with Models that have a different connection"""
+
+        # Testing on a model class
+        TestModel.__connection__ = 'cluster'
+        AnotherTestModel.__connection__ = 'cluster2'
+
+        with self.assertRaises(CQLEngineException):
+            with BatchQuery() as b:
+                TestModel.objects.batch(b).create(partition=1, cluster=1)
+                AnotherTestModel.objects.batch(b).create(partition=1, cluster=1)
+
+        TestModel.__connection__ = None
+        AnotherTestModel.__connection__ = None
+
+        with BatchQuery(connection='cluster') as b:
+            TestModel.objects.batch(b).create(partition=1, cluster=1)
+            AnotherTestModel.objects.batch(b).create(partition=1, cluster=1)
+
+        # Testing on a model instance
+        with ContextQuery(TestModel, AnotherTestModel, connection='cluster') as (tm, atm):
+            obj1 = tm.objects.get(partition=1, cluster=1)
+            obj2 = atm.objects.get(partition=1, cluster=1)
+
+            obj1.__connection__ = 'cluster'
+            obj2.__connection__ = 'cluster2'
+
+            obj1.count = 4
+            obj2.count = 4
+
+        with self.assertRaises(CQLEngineException):
+            with BatchQuery() as b:
+                obj1.batch(b).save()
+                obj2.batch(b).save()
+
+    def test_batch_query_connection_override(self):
+        """Test that we cannot override a BatchQuery connection per model"""
+
+        with self.assertRaises(CQLEngineException):
+            with BatchQuery(connection='cluster') as b:
+                TestModel.batch(b).using(connection='test').save()
+
+        with self.assertRaises(CQLEngineException):
+            with BatchQuery(connection='cluster') as b:
+                TestModel.using(connection='test').batch(b).save()
+
+        with ContextQuery(TestModel, AnotherTestModel, connection='cluster') as (tm, atm):
+            obj1 = tm.objects.get(partition=1, cluster=1)
+            obj1.__connection__ = None
+
+        with self.assertRaises(CQLEngineException):
+            with BatchQuery(connection='cluster') as b:
+                obj1.using(connection='test').batch(b).save()
+
+        with self.assertRaises(CQLEngineException):
+            with BatchQuery(connection='cluster') as b:
+                obj1.batch(b).using(connection='test').save()
+
+
+class UsingDescriptorTests(BaseCassEngTestCase):
+
+    conns = ['cluster']
+    keyspaces = ['ks1', 'ks2']
+
+    @classmethod
+    def setUpClass(cls):
+        super(UsingDescriptorTests, cls).setUpClass()
+
+        conn.unregister_connection('default')
+        conn.register_connection('fake_cluster', ['127.0.0.100'], lazy_connect=True, retry_connect=True, default=True)
+        conn.register_connection('cluster', ['127.0.0.1'])
+
+
+    @classmethod
+    def tearDownClass(cls):
+        super(UsingDescriptorTests, cls).tearDownClass()
+
+        # reset the default connection
+        conn.unregister_connection('fake_cluster')
+        conn.unregister_connection('cluster')
+        setup_connection(DEFAULT_KEYSPACE)
+
+        for ks in cls.keyspaces:
+            drop_keyspace(ks)
+
+    def setUp(self):
+        super(BaseCassEngTestCase, self).setUp()
+
+    def _reset_data(self):
+
+        for ks in self.keyspaces:
+            drop_keyspace(ks, connections=self.conns)
+
+        for ks in self.keyspaces:
+            create_keyspace_simple(ks, 1, connections=self.conns)
+        sync_table(TestModel, keyspaces=self.keyspaces, connections=self.conns)
+
+    def test_keyspace(self):
+
+        self._reset_data()
+
+        with ContextQuery(TestModel, connection='cluster') as tm:
+
+            # keyspace Model class
+            tm.objects.using(keyspace='ks2').create(partition=1, cluster=1)
+            tm.objects.using(keyspace='ks2').create(partition=2, cluster=2)
+
+            with self.assertRaises(TestModel.DoesNotExist):
+                tm.objects.get(partition=1, cluster=1)  # default keyspace ks1
+            obj1 = tm.objects.using(keyspace='ks2').get(partition=1, cluster=1)
+
+            obj1.count = 2
+            obj1.save()
+
+        with self.assertRaises(NoHostAvailable):
+            TestModel.objects.using(keyspace='ks2').get(partition=1, cluster=1)
+
+        obj2 = TestModel.objects.using(connection='cluster', keyspace='ks2').get(partition=1, cluster=1)
+        self.assertEqual(obj2.count, 2)
+
+        # Update test
+        TestModel.objects(partition=2, cluster=2).using(connection='cluster', keyspace='ks2').update(count=5)
+        obj3 = TestModel.objects.using(connection='cluster', keyspace='ks2').get(partition=2, cluster=2)
+        self.assertEqual(obj3.count, 5)
+
+        TestModel.objects(partition=2, cluster=2).using(connection='cluster', keyspace='ks2').delete()
+        with self.assertRaises(TestModel.DoesNotExist):
+            TestModel.objects.using(connection='cluster', keyspace='ks2').get(partition=2, cluster=2)
+
+    def test_connection(self):
+
+        self._reset_data()
+
+        # Model class
+        with self.assertRaises(NoHostAvailable):
+            TestModel.objects.create(partition=1, cluster=1)
+
+        TestModel.objects.using(connection='cluster').create(partition=1, cluster=1)
+        TestModel.objects(partition=1, cluster=1).using(connection='cluster').update(count=2)
+        obj1 = TestModel.objects.using(connection='cluster').get(partition=1, cluster=1)
+        self.assertEqual(obj1.count, 2)
+
+        obj1.using(connection='cluster').update(count=5)
+        obj1 = TestModel.objects.using(connection='cluster').get(partition=1, cluster=1)
+        self.assertEqual(obj1.count, 5)
+
+        obj1.using(connection='cluster').delete()
+        with self.assertRaises(TestModel.DoesNotExist):
+            TestModel.objects.using(connection='cluster').get(partition=1, cluster=1)
diff --git a/tests/integration/cqlengine/test_context_query.py b/tests/integration/cqlengine/test_context_query.py
index b3941319..0a29688d 100644
--- a/tests/integration/cqlengine/test_context_query.py
+++ b/tests/integration/cqlengine/test_context_query.py
@@ -46,6 +46,7 @@ class ContextQueryTests(BaseCassEngTestCase):
         for ks in cls.KEYSPACES:
             drop_keyspace(ks)
 
+
     def setUp(self):
         super(ContextQueryTests, self).setUp()
         for ks in self.KEYSPACES:
@@ -125,3 +126,50 @@ class ContextQueryTests(BaseCassEngTestCase):
 
             self.assertEqual(42, tm.objects.get(partition=1).count)
 
+    def test_context_multiple_models(self):
+        """
+        Tests the use of multiple models with the context manager
+
+        @since 3.7
+        @jira_ticket PYTHON-613
+        @expected_result all models are properly updated with the context
+
+        @test_category query
+        """
+
+        with ContextQuery(TestModel, TestModel, keyspace='ks4') as (tm1, tm2):
+
+            self.assertNotEqual(tm1, tm2)
+            self.assertEqual(tm1.__keyspace__, 'ks4')
+            self.assertEqual(tm2.__keyspace__, 'ks4')
+
+    def test_context_invalid_parameters(self):
+        """
+        Tests that invalid parameters are raised by the context manager
+
+        @since 3.7
+        @jira_ticket PYTHON-613
+        @expected_result a ValueError is raised when passing invalid parameters
+
+        @test_category query
+        """
+
+        with self.assertRaises(ValueError):
+            with ContextQuery(keyspace='ks2'):
+                pass
+
+        with self.assertRaises(ValueError):
+            with ContextQuery(42) as tm:
+                pass
+
+        with self.assertRaises(ValueError):
+            with ContextQuery(TestModel, 42):
+                pass
+
+        with self.assertRaises(ValueError):
+            with ContextQuery(TestModel, unknown_param=42):
+                pass
+
+        with self.assertRaises(ValueError):
+            with ContextQuery(TestModel, keyspace='ks2', unknown_param=42):
+                pass
\ No newline at end of file