The Tolpuddle Martyrs were a group of 19th century British labourers who formed a trade union, and were subsequently arrested and sentenced to transportation to Australia.

The Reform Act of 1832 made unions legal, and that year six men from Tolpuddle in Dorset founded the Friendly Society of Agricultural Labourers to protest against the gradual lowering of wages in the 1830s. They refused to work for less than 10 shillings a week, although by this time wages were as low as 6 shillings a week. The society, led by George Loveless , a Methodist local preacher, met in the house of Thomas Standfield.

In 1834 a local landowner wrote to the Prime Minister, Lord Melbourne, to complain about the union, invoking an obscure law from 1797 prohibiting people from swearing oaths to each other, which the Friendly Society had done. James Brine, James Hammett, George Loveless, George's brother James, George's brother in-law Thomas Standfield, and Thomas' son John Standfield were arrested, found guilty, and transported to Australia.

They became popular heroes and were released in 1836, with the support of Lord John Russell who had recently become Home Secretary. George Loveless was later involved in the Chartist Movement, while the others moved to London, Ontario, Canada, where there is now a monument in their honour. There was also a monument erected in their honour in Tolpuddle in 1934, and a sculpture of the martyrs made in 2001 stands in the village in front of the Martyrs Museum there.

An annual festival is held in Tolpuddle, organised by the Trades Union Congress (TUC) featuring a parade of banners from many trade unions, a memorial service, speeches and music. Recent festivals have featured speakers such as Tony Benn and musicians such as Billy Bragg, as well as others from all around the world. The festival is usually held in the third week of July.