Complex sentence: Colonel John Stoughton Dennis (19 October, 1820--7 July, 1885) was a Canadian surveyor, officer of the Canadian militia, and civil servant noted for his role in precipitating the Red River Rebellion by his 1869 surveys of the Red River Settlement.
Split into simpler sentences: Colonel John Stoughton Dennis (19 October, 1820--7 July, 1885) was a Canadian surveyor, officer of the Canadian militia, and civil servant. Dennis is noted for his role in precipitating the Red River Rebellion by his 1869 surveys of the Red River Settlement.