Causantín or Constantín mac Fergusa (789–820) was king of the Picts, in modern Scotland, from 789 until 820. He was until the Victorian era sometimes counted as Constantine I of Scotland; the title is now generally given to Causantín mac Cináeda. He is credited with having founded the church at Dunkeld which later received relics of St Columba from Iona.
- Occupation
- monarch
- Position held
- list of kings of the Picts, list of kings of Dál Riata
- Born
- 701
- Died
- 820
