English children are taught too much about Adolf Hitler and Nazi Germany in school history lessons, the country's education watchdog said on Thursday.

The Qualifications and Curriculum Authority said the teaching of the subject for teenage pupils was dominated by 20th Century dictatorships and other topics such as England's Tudor monarchs like Henry VIII who ruled during the 16th century.

"There has been a gradual narrowing and 'Hitlerisation' of post-14 history," the QCA said in its annual report, adding that there was also too little emphasis on black or multi-ethnic aspects of British history.

Chief executive Ken Boston said lessons often failed to give an impression of life in post-war Germany.

"While that period was absolutely critically important to us and we need to understand it and learn from it," he told the BBC, "history didn't end in Germany with the death of a dictator: the modern era began in Germany from that point."

Britons' fascination with Hitler and World War Two was part of the reason for teachers choosing the topic, according to Historical Association secretary Sean Lang.

"The main reason, to put it really bluntly, is because Hitler sells, as any publisher will tell you," he told the BBC.

This prejudice irked one former German ambassador to London so much that he lambasted Britons for their "profound ignorance" of modern Germany when he left his post in 1999.

Gebhardt von Moltke, who worked in London until 1999, said he had been particularly offended by references to all Germans being Nazis as two of his uncles had been executed for being leading members of the resistance to Hitler.