The Duchy of Oldenburg (German: Herzogtum Oldenburg) — named after its capital, the town of Oldenburg — was a state in the north-west of present-day Germany. Oldenburg survived from 1180 until 1810 when it was annexed by First French Empire. It was located near the mouth of the River Weser. Its ruling family, the House of Oldenburg, also came to rule in Denmark, Norway, Sweden, Greece and Russia, and the heirs of a junior line of the Greek branch are, through Prince Philip, Duke of Edinburgh, likely to inherit the thrones of the United Kingdom and the Commonwealth realms after the death or abdication of Queen Elizabeth II.