diff --git a/libs/core/tests/unit_tests/fake/memory.py b/libs/core/tests/unit_tests/fake/memory.py
deleted file mode 100644
index d8431fa8599..00000000000
--- a/libs/core/tests/unit_tests/fake/memory.py
+++ /dev/null
@@ -1,25 +0,0 @@
-from typing import List
-
-from langchain_core.chat_history import (
-    BaseChatMessageHistory,
-)
-from langchain_core.messages import BaseMessage
-from langchain_core.pydantic_v1 import BaseModel, Field
-
-
-class ChatMessageHistory(BaseChatMessageHistory, BaseModel):
-    """In memory implementation of chat message history.
-
-    Stores messages in an in memory list.
-    """
-
-    messages: List[BaseMessage] = Field(default_factory=list)
-
-    def add_message(self, message: BaseMessage) -> None:
-        """Add a self-created message to the store"""
-        if not isinstance(message, BaseMessage):
-            raise ValueError
-        self.messages.append(message)
-
-    def clear(self) -> None:
-        self.messages = []
diff --git a/libs/core/tests/unit_tests/runnables/test_history.py b/libs/core/tests/unit_tests/runnables/test_history.py
index 60883f9a324..69c35524df7 100644
--- a/libs/core/tests/unit_tests/runnables/test_history.py
+++ b/libs/core/tests/unit_tests/runnables/test_history.py
@@ -3,6 +3,7 @@ from typing import Any, Callable, Dict, List, Optional, Sequence, Union
 from langchain_core.callbacks import (
     CallbackManagerForLLMRun,
 )
+from langchain_core.chat_history import InMemoryChatMessageHistory
 from langchain_core.language_models.chat_models import BaseChatModel
 from langchain_core.messages import AIMessage, BaseMessage, HumanMessage, SystemMessage
 from langchain_core.outputs import ChatGeneration, ChatResult
@@ -11,11 +12,10 @@ from langchain_core.runnables.base import RunnableLambda
 from langchain_core.runnables.config import RunnableConfig
 from langchain_core.runnables.history import RunnableWithMessageHistory
 from langchain_core.runnables.utils import ConfigurableFieldSpec
-from tests.unit_tests.fake.memory import ChatMessageHistory
 
 
 def test_interfaces() -> None:
-    history = ChatMessageHistory()
+    history = InMemoryChatMessageHistory()
     history.add_message(SystemMessage(content="system"))
     history.add_user_message("human 1")
     history.add_ai_message("ai")
@@ -26,12 +26,14 @@ def test_interfaces() -> None:
 def _get_get_session_history(
     *,
     store: Optional[Dict[str, Any]] = None,
-) -> Callable[..., ChatMessageHistory]:
+) -> Callable[..., InMemoryChatMessageHistory]:
     chat_history_store = store if store is not None else {}
 
-    def get_session_history(session_id: str, **kwargs: Any) -> ChatMessageHistory:
+    def get_session_history(
+        session_id: str, **kwargs: Any
+    ) -> InMemoryChatMessageHistory:
         if session_id not in chat_history_store:
-            chat_history_store[session_id] = ChatMessageHistory()
+            chat_history_store[session_id] = InMemoryChatMessageHistory()
         return chat_history_store[session_id]
 
     return get_session_history
@@ -51,7 +53,7 @@ def test_input_messages() -> None:
     output = with_history.invoke([HumanMessage(content="good bye")], config)
     assert output == "you said: hello\ngood bye"
     assert store == {
-        "1": ChatMessageHistory(
+        "1": InMemoryChatMessageHistory(
             messages=[
                 HumanMessage(content="hello"),
                 AIMessage(content="you said: hello"),
@@ -76,7 +78,7 @@ async def test_input_messages_async() -> None:
     output = await with_history.ainvoke([HumanMessage(content="good bye")], config)
     assert output == "you said: hello\ngood bye"
     assert store == {
-        "1_async": ChatMessageHistory(
+        "1_async": InMemoryChatMessageHistory(
             messages=[
                 HumanMessage(content="hello"),
                 AIMessage(content="you said: hello"),
@@ -485,9 +487,11 @@ def test_using_custom_config_specs() -> None:
     runnable = RunnableLambda(_fake_llm)
     store = {}
 
-    def get_session_history(user_id: str, conversation_id: str) -> ChatMessageHistory:
+    def get_session_history(
+        user_id: str, conversation_id: str
+    ) -> InMemoryChatMessageHistory:
         if (user_id, conversation_id) not in store:
-            store[(user_id, conversation_id)] = ChatMessageHistory()
+            store[(user_id, conversation_id)] = InMemoryChatMessageHistory()
         return store[(user_id, conversation_id)]
 
     with_message_history = RunnableWithMessageHistory(
@@ -524,7 +528,7 @@ def test_using_custom_config_specs() -> None:
         AIMessage(content="you said: hello"),
     ]
     assert store == {
-        ("user1", "1"): ChatMessageHistory(
+        ("user1", "1"): InMemoryChatMessageHistory(
             messages=[
                 HumanMessage(content="hello"),
                 AIMessage(content="you said: hello"),
@@ -542,7 +546,7 @@ def test_using_custom_config_specs() -> None:
         AIMessage(content="you said: goodbye"),
     ]
     assert store == {
-        ("user1", "1"): ChatMessageHistory(
+        ("user1", "1"): InMemoryChatMessageHistory(
             messages=[
                 HumanMessage(content="hello"),
                 AIMessage(content="you said: hello"),
@@ -562,7 +566,7 @@ def test_using_custom_config_specs() -> None:
         AIMessage(content="you said: meow"),
     ]
     assert store == {
-        ("user1", "1"): ChatMessageHistory(
+        ("user1", "1"): InMemoryChatMessageHistory(
             messages=[
                 HumanMessage(content="hello"),
                 AIMessage(content="you said: hello"),
@@ -570,7 +574,7 @@ def test_using_custom_config_specs() -> None:
                 AIMessage(content="you said: goodbye"),
             ]
         ),
-        ("user2", "1"): ChatMessageHistory(
+        ("user2", "1"): InMemoryChatMessageHistory(
             messages=[
                 HumanMessage(content="meow"),
                 AIMessage(content="you said: meow"),
@@ -596,9 +600,11 @@ async def test_using_custom_config_specs_async() -> None:
     runnable = RunnableLambda(_fake_llm)
     store = {}
 
-    def get_session_history(user_id: str, conversation_id: str) -> ChatMessageHistory:
+    def get_session_history(
+        user_id: str, conversation_id: str
+    ) -> InMemoryChatMessageHistory:
         if (user_id, conversation_id) not in store:
-            store[(user_id, conversation_id)] = ChatMessageHistory()
+            store[(user_id, conversation_id)] = InMemoryChatMessageHistory()
         return store[(user_id, conversation_id)]
 
     with_message_history = RunnableWithMessageHistory(
@@ -635,7 +641,7 @@ async def test_using_custom_config_specs_async() -> None:
         AIMessage(content="you said: hello"),
     ]
     assert store == {
-        ("user1_async", "1_async"): ChatMessageHistory(
+        ("user1_async", "1_async"): InMemoryChatMessageHistory(
             messages=[
                 HumanMessage(content="hello"),
                 AIMessage(content="you said: hello"),
@@ -653,7 +659,7 @@ async def test_using_custom_config_specs_async() -> None:
         AIMessage(content="you said: goodbye"),
     ]
     assert store == {
-        ("user1_async", "1_async"): ChatMessageHistory(
+        ("user1_async", "1_async"): InMemoryChatMessageHistory(
             messages=[
                 HumanMessage(content="hello"),
                 AIMessage(content="you said: hello"),
@@ -673,7 +679,7 @@ async def test_using_custom_config_specs_async() -> None:
         AIMessage(content="you said: meow"),
     ]
     assert store == {
-        ("user1_async", "1_async"): ChatMessageHistory(
+        ("user1_async", "1_async"): InMemoryChatMessageHistory(
             messages=[
                 HumanMessage(content="hello"),
                 AIMessage(content="you said: hello"),
@@ -681,7 +687,7 @@ async def test_using_custom_config_specs_async() -> None:
                 AIMessage(content="you said: goodbye"),
             ]
         ),
-        ("user2_async", "1_async"): ChatMessageHistory(
+        ("user2_async", "1_async"): InMemoryChatMessageHistory(
             messages=[
                 HumanMessage(content="meow"),
                 AIMessage(content="you said: meow"),