They believed that it was desirable to support the United Kingdom in World War I against "Prussian militarism".
[1] In 1919, the group changed its name to the Social Democratic Federation, reverting to the name that the British Socialist Party had used.
At one point eleven MPs were members, but after Hyndman died in 1921, the group gradually dissolved into the Labour Party.
[3] The party finally disbanded in 1939 due to a lack of funds, although some remaining members formed a "Social Democratic Fellowship".
[4] Other prominent members included Henry W. Lee, Hunter Watts, John Stokes and Joseph Burgess.