United or confederated states have in many cases adopted a jack representing their national union. The best known is the Union Jack of the United Kingdom's Royal Navy, composed in 1606 by joining together the flags of England and Scotland. When the Kingdom of Ireland merged with Great Britain in 1801, a red saltire (Saint Patrick's Cross) was added to form the present Union Flag. The design of the UK's Union Jack probably inspired later jacks of other states, such as Russia and Sweden–Norway. The Russian jack in its turn inspired the jacks of Bulgaria, Estonia, and Latvia.