<P> In the 19th century the role of the foreskin in erotic sensation was well understood by physicians who wanted to cut it off precisely because they considered it the major factor leading boys to masturbation . The Victorian physician and venereologist William Acton (1814--1875) damned it as "a source of serious mischief", and most of his contemporaries concurred . Both opponents and supporters of circumcision agreed that the significant role the foreskin played in sexual response was the main reason why it should be either left in place or removed . William Hammond, a Professor of Mind in New York in the late 19th century, commented that "circumcision, when performed in early life, generally lessens the voluptuous sensations of sexual intercourse", and both he and Acton considered the foreskin necessary for optimal sexual function, especially in old age . Jonathan Hutchinson, English surgeon and pathologist (1828--1913), and many others, thought this was the main reason why it should be excised . </P> <P> Born in the United Kingdom during the late - nineteenth century, John Maynard Keynes and his brother Geoffrey, were both circumcised in boyhood due to parents' concern about their masturbatory habits . Mainstream pediatric manuals continued to recommend circumcision as a deterrent against masturbation until the 1950s . </P> <P> Infant circumcision was taken up in the United Kingdom, the United States, Australia, New Zealand, and the English - speaking parts of Canada . Although it is difficult to determine historical circumcision rates, one estimate of infant circumcision rates in the United States holds that 30% of newborn American boys were being circumcised in 1900, 55% in 1925, and 72% in 1950 . </P> <P> In South Korea, circumcision was largely unknown before the establishment of the United States trusteeship in 1945 and the spread of American influence . More than 90% of South Korean high school boys are now circumcised at an average age of 12 years, which makes South Korea a unique case . However circumcision rates are now declining in South Korea . </P>

When did circumcision become popular in the us
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