The Royal Burgh of Haddington () is a town in East Lothian, Scotland. It is the main administrative, cultural and geographical centre for East Lothian, which was known officially as Haddingtonshire before 1921. It lies about east of Edinburgh. The name Haddington is Anglo-Saxon, dating from the 6th or 7th century AD when the area was incorporated into the kingdom of Bernicia. The town, like the rest of the Lothian region, was ceded by King Edgar of England and became part of Scotland in the 10th century. Haddington received burghal status, one of the earliest to do so, during the reign of David I (1124–1153), giving it trading rights which encouraged its growth into a market town.