A British Union Flag (pre-1801 pattern) made of silk and hand-sewn. An old label says this is a 'jack' but it is perhaps a large a boat flag.

This flag predates the Act of Union of 2 July 1800 which amalgamated the parliaments of Great Britain and Ireland (the United Kingdom of Great Britain and Ireland came into existence in the following year). The Union Flag and ensigns were altered to include a symbol for Ireland. The emblem chosen was the 'Cross of St Patrick', a red saltire (diagonal cross) originally part of the arms of the Anglo-Irish Fitzgerald family. This Union Flag shows the original 1606 design before the red saltire was added.