Charles Colmore Grant, 7th Baron de Longueuil was the son of Charles James Irwin Grant, 6th Baron de Longueuil and Harriet Cregoe-Colmore.
[1] In 1880, he claimed a royal recognition of his right to the barony of Longueuil.
By the treaty of Quebec the sovereignty of Canada passed from the Kings of France to the Kings of Great Britain but with the reservation that all rights and privileges "of what kind soever" should be reserved and secured to all individuals of French descent to which they had been entitled under the previous regime.
[2] Queen Victoria was graciously pleased to recognise the claim of Charles Colmore Grant to the title of Baron de Longueuil.
[1][4] He was without issue and his half-brother Reginald Charles succeeded him.