[2] His great-grandfather had settled in County Kerry in 1666, purchasing land at Burnham, near Dingle, and had served as a Member of the Irish House of Commons.
In 1790 he built a new stately home for his family overlooking Dingle harbour, called Burnham Manor.
On 18 June 1793, over 4,000 people marched in Dingle to protest against high rents and the establishment of a local militia.
Mullins, who assumed responsibility for the town on behalf of the Crown, brought in 70 soldiers from Limerick to break up the demonstration.
[4] This was largely due to the help he and his son, William, had given to Lord Castlereagh in securing the passage of the Irish Act of Union of 1800.