Sir Harry Lauder (/ˈlɔːdər/; 4 August 1870 – 26 February 1950) was a Scottish singer, comedian and actor. Popular in both music hall and vaudeville theatre traditions; he achieved international success.

He was described by Sir Winston Churchill as "Scotland's greatest ever ambassador", who "by his inspiring songs and valiant life, rendered measureless service to the Scottish race and to the British Empire". He became a familiar worldwide figure deploying his kilt and cromach (walking stick) as icons of Scottishness to huge acclaim, especially in America. Among his most popular songs were "Roamin' in the Gloamin'", "A Wee Deoch-an-Doris", "The End of the Road" and, a particularly big hit for him, "I Love a Lassie".

Lauder's understanding of life, its pathos and joys, earned him his popularity. Beniamino Gigli commended his singing voice and clarity. Lauder usually performed in full Highland regalia—kilt, sporran, tam o' shanter, and twisted walking stick, and sang Scottish-themed songs. By 1911 Lauder had become the highest-paid performer in the world, and was the first artist from both Britain and Scotland to sell a million records; by 1928 he had sold double that. He raised vast amounts of money for the war effort during the First World War, for which he was knighted by George V in 1919. He went into semi-retirement in the mid-1930s, but briefly emerged to entertain troops in the Second World War. By the late 1940s he was suffering from long periods of ill-health; he died in his native Scotland in 1950.

Lauder was born on 4 August 1870 in his maternal grandfather's house in Portobello, Edinburgh, Scotland, the eldest of seven children. By the time of the 1871 census he and his parents were living at 1 Newbigging Veitchs Cottages, Inveresk. His father, John Lauder, was the grandson of George Lauder of Inverleith Mains & the St Bernard's Well estate, Edinburgh. He claimed in his autobiography that his family were descendants of the feudal barons the Lauders of the Bass; and his mother, Isabella Urquhart MacLeod née McLennan, was born in Arbroath to a family from the Black Isle. John and Isabella married on 26 August 1870. Lauder's father moved to Newbold, Derbyshire, in early 1882 to take up a job designing porcelain, but died on 20 April from pneumonia. Isabella, left with little more than John's life insurance proceeds of £15, moved with the children to be with her family in Arbroath. To finance his education beyond age 11, Harry worked part-time at a flax mill. He made his first public appearance, singing, at a variety concert at Oddfellows' Hall in Arbroath when he was 13 years old, winning first prize for the night (a watch).

In 1884 the family went to Hamilton, South Lanarkshire, to live with Isabella's brother, Alexander, who found Harry employment at Eddlewood Colliery at ten shillings per week; he kept this job for a decade.

On 8 January 1910, the Glasgow Evening Times reported that Lauder had told the New York World that, during his mining career:

I was entombed once for 6 long hours. It seemed like 6 years. There were no visible means of getting out either – we had just to wait. I was once right next to a cave-in when my fire boss was buried alive. As we were working and chatting a big stone twice as big as a trunk came tumbling down on my mate from overhead, doubling him like a jack-knife. It squeezed his face right down on the floor. God knows I wasn't strong enough to lift that rock alone, but by superhuman efforts I did. This gave him a chance to breathe and then I shouted. Some men 70 yards away heard me and came and got him out alive. A chap who worked beside me was killed along with 71 others at Udston, and all they could identify him with was his pin leg. I wasn't there that day.

Lauder said he was "proud to be old coal-miner" and in 1911, became an outspoken advocate, "pleading the cause of the poor pit ponies" to Winston Churchill, when introduced to him at the House of Commons and later reported to the Tamworth Herald that he "could talk for hours about my wee four-footed friends of the mine. But I think I convinced that the time has now arrived when something should be done by the law of the land to improve the lot and working conditions of the patient, equine slaves who assist so materially in carrying on the great mining industry of this country."