My wife's family are related to the Sanger circus family. (Lord George was a cousin of wife's grandmother, I think it was.) There are ample references to the circus in early encylopaediae. The first of the following is from the early part of the century. The second is from an edition from the 1960s. I hope it is of help to someone.
Sanger, GEORGE (1827-1911):
Circus proprietor and showman, who called himself Lord George Sanger. He was born at Newbury,Berkshire, Dec. 23, 1827, the son of a travelling showman in a small way, who had been a seaman on board the Victory, at Trafalgar.As a youth George led a wandering life with his parents, and at Stepney Fair, in 1848, he met Nellie Chapman, then performing with Wombwell's lions, and married her in 1850.
He took over the circus which his father, John Sanger, had started in 1821, and made this a very profitable concern. One of his great successes was his spectacle of Mazeppa, the name part of which he impersonated over9,000 times.In l871 Sanger purchased Astley's amphitheatre andmenagerie, and about the same time leased the Agricultural Hall, Islington.Besides these, heran circuses at Birmingham, Liverpool, Glasgow, Dundee, Aberdeen, Bath, Bristol, and Plymouth. In 1905, he disposed of his circus property. He was shot dead by one of his employees, Nov. 28, 1911.
(See Seventy Years a Showman, L. G. Sanger, 1914.)
Sanger, JOHN (1816-1889):
English circus proprietor, was born at Chew Magna, Somerset, in 1816, the son of an old sailor who had turned showman. In 1845 he started with his brother George a conjuring exhibition at Birmingham. The venture was successful, and the brothers, who had been interested spectators of the equestrian performances at Astley's amphitheatre, London, then started touring the country
with a circus entertainment consisting of a horse and pony and three or four human performers.
Eventually .John and George Sanger became lessees of the Agricultural Hall, London, and there produced a large number of elaborate spectacles. In 1871 the Sangers leased Astley's where they gave an equestrian pantomime every winter, touring in the summer with a large circus.
Subsequently the partnership was dissolved, each brother producing his own show. John Sanger died while touring, at Ipswich on Aug 22, 1889, the business being continued by his son.