Cathal mac Aodha Mág Samhradháin (anglicised Charles McGovern) or Cathal Mág Samhradháin was chief of the McGovern Clan and Baron or Lord of Tullyhaw barony, County Cavan from 1504 until his death in 1512.
Cathal's brothers were Toirdealbhach (who was Tánaiste of the clan and died in 1512), Tadhg (d. 1498) and Maghnus ‘The Cleric’ (d. 1498).
There was internecine warfare between the McGovern clan and the reigning chief, Domhnall ‘Bernach’ Mág Samhradháin, was slain on 15 February 1496 by Cathal and others in Templeport Church.
On 28 September 1498 two of Cathal's brothers, Tadhg and Manus the priest, were killed in a Maguire raid on the castle of Ballymagauran.
The Annals of Ulster for 1505 state- The daughter of Mag Samradhain, namely, Una, wife of Failghe, son of Domnall Ua Raighilligh the White, died this year.
The internecine warfare continued in 1507 when Cathal's brother, Toirdealbhach, the Tánaiste of the clan, killed the son of a previous chief Domhnall ‘Bernach’ Mág Samhradháin.
In 1512 there was conflict with Tomás Mág Samhradháin, the Fourth who was the leader of a dissident sept within the McGovern clan and was attempting to claim the chieftainship.