The District of Warsaw (of Armia Krajowa) - one of territorial organisational units of Armia Krajowa, which covered the territory of Warsaw and its close neighbourhood i.e. the Powiat of Warsaw. Military units belonging to that district took part in the Warsaw Uprising of 1944.
The rest of the territory of Mazovia, i.e. the Warsaw Voivodship, was included into a larger organisational unit, the Area of Warsaw of Armia Krajowa.
Details: Organisational structure of Armia Krajowa, table of organisational units: "Independent districts" -> "Warsaw".