William Joyce (April 24, 1906–January 3, 1946), known as Lord Haw-Haw was a fascist politician and Nazi propaganda broadcaster to the United Kingdom during World War II.

He was born in New York, to Irish parents who had taken United States nationality. A few years after his birth, the family returned to Galway, Ireland. He attended St. Ignatius College, Galway, from 1915 to 1921. Though the family were Roman Catholic, they were strongly unionist. William Joyce later claimed to have aided the Black and Tans.

Fearing reprisal attacks, the Joyce family left for London after the establishment of the Irish Free State, where Joyce applied to Birkbeck College of the University of London and to enter the Officer Training Corps. At Birkbeck Joyce developed an interest in fascism, and he joined the British Fascisti of Rotha Lintorn-Orman. While stewarding a Conservative Party meeting, Joyce was involved in a fight and received a deep razor slash to his cheek. Joyce joined the British Union of Fascists under Sir Oswald Mosley in 1932, and swiftly became a leading speaker, praised for his power of oratory.

He was instrumental in changing the full name of the BUF to British Union of Fascists and National Socialists in 1936. He stood as a BUF candidate in the 1937 elections to the London County Council. However, when Mosley drastically reduced the BUF staff shortly after the elections (sacking Joyce), he left to form a breakaway organization, the National Socialist League ,

In late August 1939, shortly before World War II commenced, he and his wife, Margaret, fled to Germany. He had been tipped off, probably by Maxwell Knight of MI5, that the British authorities intended to detain him under Defence Regulation 18B. Joyce became a naturalized German in 1940.

The name 'Lord Haw-Haw of Zeesen' was coined by the pseudonymous Daily Express radio critic Jonah Barrington in 1939, but this referred initially to Wolf Mitler . When Joyce became the best-known propaganda broadcaster the nickname transferred to him. Besides broadcasting, Joyce's duties included distributing propaganda among British prisoners of war, whom he tried to recruit into the British Free Corps, as a branch of the Waffen SS. He wrote a book, Twilight over England, that was promoted by the German Ministry of Propaganda.

At the end of the war, he was captured by British forces near the German-Danish border at Flensburg. He was interecpted by soldiers who initially thought he was a German civilian, however his voice betrayed him, and he was recognised and returned to Britain. During the course of his arrest he was shot in the leg when the soldiers thought he was going for a gun.

He was tried on three counts of high treason. These were as follows:

• William Joyce, on September 18 1939, and on numerous other days between 18 September 1939 and 29 May 1945 did aid and assist the enemies of the King by broadcasting to the King's subjects propaganda on behalf of the King's enemies.
• William Joyce, on 26 September 1940, did aid and comfort the King's enemies by purporting to be naturalised as a German citizen.
• William Joyce, on 18 September 1939 and on numerous other days between 18 September 1939 and 2 July 1940 did aid and assist the enemies of the King by broadcasting to the King's subjects propaganda on behalf of the King's enemies.

During the processing of the charges Joyce's American nationality came to light, and it seemed that he would have to be acquitted, based not upon innocence of the charges of aiding the Nazi war effort but rather a lack of jurisdiction; he could not be convicted of betraying a country that was not his own. However, Attorney General Sir Hartley Shawcross successfully argued that Joyce's possession of a British passport, even though he had lied about his nationality in order to get it, entitled him to British diplomatic protection in Germany and therefore he owed allegiance to the King. It was on this technicality, confirmed by the Court of Appeal and the House of Lords, that Joyce was convicted and sentenced to death.

Joyce was executed by famed hangman Albert Pierrepoint on January 3 1946, at Wandsworth Prison. The Crown considered trying his wife, Margaret, as well, but a secret memo recommended clemency for her.

William and Margaret Joyce had two daughters, one of whom is Heather Landolo .

Joyce was reinterred in 1976 at New Cemetery in Bohermore , County Galway, Ireland.