Paintings by renowned Bradford artist and friend of the stars Sir William Rothenstein are to go under the hammer later this month.

They are part of his granddaughter's collection and many are up for sale for the first time.

Sir William, who died at the age of 73 in 1945, was a close friend of Oscar Wilde and was most famous for his portraits of prominent figures including Albert Einstein, Thomas Hardy and George Bernard Shaw.

The son of a German wool merchant, Sir William lived on Manningham Lane and attended Bradford Grammar School with contemporaries Sir Frank Dyson and Frederick Delius.

At school he had to draw pictures instead of doing lines as punishment.

Aged just 16, he moved to London and went on to serve as a war artist during the first and second world wars.

Sir William was also said to be a huge admirer of the Brontes. Two of his friends were sons of the vicar who succeeded the Reverend Patrick Bronte in Haworth.

His painting Woman in a Black Bonnet in Paris is estimated to raise between £5,000 and £7,000 when auctioned at Sotheby's in London.

In 1972 it featured in a centenary exhibition of his work at Bradford City Art gallery.

A work called Mother and Child, signed and dated by the artist in 1902, depicts his wife Alice and first child John. That is expected to raise between £800 and £1,200. A reversed and developed composition now hangs in the Tate Gallery.

The auction is also expected to feature a full-length portrait of theatre impressario Max Beerbohm of 1900 estimated to fetch between £10,000 and £15,000.

They were lifelong friends and Beerbohm gave the address at a memorial service to Sir William.

One critic wrote after meeting Sir William: "I was shocked by the flippancy of his conversation and the elegance of his dress - but when the subject of painting came up I thought I was listening to a discourse by an Old Testament prophet."

Rothenstein first met Oscar Wilde when the writer visited his studio unannounced, but they went on to become firm friends.

The paintings are part of a collection owned by his granddaughter, Lucy Dyvenor, which are up for sale on February 26 at Sotheby's Olympia in London.

Freya Mitton, modern British picture specialist at Sotheby's Olympia, said: "The works on offer chronicle the significant developments in British art during the period 1819 to 1945 and show the influences of the Royal College of Art under Sir William Rothenstein in the 1920s."

Sir William's son John was director of the Tate from 1938-64.