Karl Albert Staaff (21 January 1860 – 4 October 1915) was a Swedish liberal politician and lawyer who served as the Prime Minister of Sweden from 1905 to 1906 and again from 1911 to 1914.

His successor as party leader, Nils Edén, eventually managed to carry this further into universal suffrage in 1918–1919, including for women.

In 1912, the period of leave that women were allowed following a child's birth was extended to six weeks, and in 1913 a tax-financed pension scheme was introduced.

An intense smear campaign was launched against him, picturing him as the destroyer of Swedish tradition and society: wealthy Stockholmers could even buy ashtrays shaped as his head.

His staunch anti-military politics led to the greatest fundraiser up to that time in Swedish history – funds for the 12 million kronor coastal battleship HSwMS Sverige were raised in 1912 in just a few months.