Ambrose was born in Warsaw in 1896, when it was part of the Russian Empire. After a time the family moved to London. They were Jewish, his father being registered as a “Dealer in rags” in the 1911 UK census, where Ambrose was named as “Barnett’ (a “Violin musician student”). He began playing the violin while young, and travelled to New York with his aunt. He began playing professionally, first for Emil Coleman at New York’s Reisenweber’s restaurant, then in the Palais Royal’s big band. After making a success of a stint as bandleader, at the age of 20 he was asked to put together and lead his own fifteen-piece band. After a dispute with his employer, he moved his band to another venue, where they enjoyed considerable popularity.

While at the Palais Royal, on 5 June 1918, he registered for the draft (Local Board Division 169, City of NY NY, 144 St Nicholas Ave; Registration 232). He gave as his date of birth 11 September 1896; place of birth Warsaw, Russia; nationality Russian; father’s birthplace Grietza, Russia; place of employment Palais Royal, 48th Street & Broadway; nearest relative Mrs Becky Ambrose, mother, 56 “Blaksley” Street, London, England. He signed as “Bert Ambrose”. The registrar recorded medium height, medium build, brown hair, brown eyes and no physical disability that would render him exempt from the draft.

In 1922, Ambrose returned to London, where he was engaged by the Embassy Club to form a seven-piece band. He stayed at the Embassy for two years, before walking out on his employer to take up a much more lucrative job at the Clover Gardens in New York. After a year there, besieged by continual pleas to return from his ex-employer in London, in 1925 he was finally persuaded to go back by a cable from the Prince of Wales: “The Embassy needs you. Come back—Edward”.

This time Ambrose stayed at the Embassy Club until 1927. The club had a policy of not allowing radio broadcasts from its premises, however, and this was a major drawback for an ambitious bandleader, largely because the fame gained by radio work helped a band to gain recording contracts (Ambrose’s band had been recorded by Columbia Records in 1923, but nothing had come of this). He therefore accepted an offer by the May Fair Hotel, with a contract that included broadcasting. His annual salary from this establishment alone was £10,000.

During his time at the Embassy, he married “Kathryn Lucille otherwise Kitty Brady”, a 24-year-old Irish-American from New Jersey, on 20 January 1924. Oddly, he is named and signed as “Bernard Ambrose”, a 27-year-old “Musical Director”, on the marriage certificate. They had two daughters, Patricia S (b. 1931) and Monica J (b. 1933).

In 1933, Ambrose was asked to accept a cut in pay at the May Fair; refusing, he went back to the Embassy Club, and after three years there (and a national tour), he rejected American offers and returned to the May Fair in 1936. He then went into partnership with Jack Harris, an American bandleader, and in 1937 they bought a club together, Ciro’s Club. For a period of three months, they employed Art Tatum. Ambrose and Harris alternated performances at Ciro’s until a disagreement led to the rupture of their partnership. Ambrose then worked at the Café de Paris until the outbreak of the Second World War, when he again went on tour.

His major discovery in the years leading up to the war was the singer Vera Lynn, who sang with his band from 1937 to 1940 and, during the war, became known as the “Forces’ Sweetheart”. Lynn married Harry Lewis, a clarinettist in the band, in 1939. Other singers with the Ambrose band included Sam Browne, Elsie Carlisle, Denny Dennis, who recorded a number of duets with Vera Lynn, Max Bacon (also the band’s drummer), Evelyn Dall and Anne Shelton, with whom “When That Man is Dead and Gone”, a jibe at Adolf Hitler, written by Irving Berlin, was recorded in 1941. Ambrose’s signature tune was “When Day is Done”.

After a short period back at the May Fair Hotel, Ambrose retired from performing in 1940, although he and his orchestra continued to make records for Decca until 1947. Several members of his band became part of the Royal Air Force band, the Squadronaires, during the war. Ambrose’s retirement was not permanent, however, and he formed and toured with the Ambrose Octet, and dabbled in management.

Ambrose was commemorated in 2005 by a blue plaque unveiled on the May Fair Hotel.