[Home](./index.md) > [@firebase/firestore](./firestore.md) > [lite](./firestore_lite.md) > [initializeFirestore](./firestore_lite.initializefirestore.md) ## initializeFirestore() function Initializes a new instance of Cloud Firestore with the provided settings. Can only be called before any other functions, including [getFirestore()](./firestore_.getfirestore.md). If the custom settings are empty, this function is equivalent to calling [getFirestore()](./firestore_.getfirestore.md). Signature: ```typescript export declare function initializeFirestore(app: FirebaseApp, settings: Settings): FirebaseFirestore; ``` ## Parameters | Parameter | Type | Description | | --- | --- | --- | | app | [FirebaseApp](./app.firebaseapp.md) | The [FirebaseApp](./app.firebaseapp.md) with which the Firestore instance will be associated. | | settings | [Settings](./firestore_lite.settings.md) | A settings object to configure the Firestore instance. | Returns: [FirebaseFirestore](./firestore_lite.firebasefirestore.md) A newly initialized Firestore instance.