Yaphank is a community in the south part of the Town of Brookhaven. It is served by the Longwood Central School District, except for extreme southwestern Yaphank, which is served by the South Country Central School District.
In the mid 18th century, a man named John Homan built two mills along the Carmans River, which runs directly through the center of the town. These two mills inspired the first name for the town: Millville. The translator/author Mary Louise Booth was born in Millville in 1831. In 1846 a post office was opened in the town, but because there were thirteen other towns named "Millville" in New York state at the time, the town was renamed "Yaphank", from the local Native American word Yamphanke, meaning "bank of a river".
In 1843 the Long Island Rail Road built a railroad station in Yaphank (still named Millville at the time), and virtually overnight the small mill town became a major commercial center. By 1875, Yaphank had two grist mills, two lumber mills, two blacksmith shops, a printing office, an upholstery shop, a stagecoach line, two physicians, a shoe shop, two wheelwright shops, a meat market, a dressmaker and a general store.
Today, Yaphank is home to about half of those industries. The grist mills, blacksmith, physician, shoe shop, wheelwright shops, meat markets and the dressmakers are long gone, although the rail road station is still here along with the general stores.
Today, Yaphank holds three delis, one pizza shop, a shooting supply company, a skeet range, a bank, and Dawn House & Building Movers, a house moving company.
Yaphank was the home of Camp Upton, which was used as a boot camp in 1917. In 1947, the U.S. Department of War transferred the Camp Upton site to the Atomic Energy Commission, and it now serves as the home of Brookhaven National Laboratory. Before the end of World War I, more than 30,000 men received their basic training there. Perhaps the most notable person to have trained at Camp Upton was the songwriter Irving Berlin. It was there he composed the musical comedy revue Yip Yip Yaphank, which had a brief run on Broadway.
Yaphank was also home to Camp Siegfried, a summer camp which taught Nazi ideology. It was owned and operated by the German American Bund, an American Nazi organization devoted to promoting a favorable view of Nazi Germany. Camp Siegfried was one of many such camps in the US in the 1930s, including Camp Hindenberg in Grafton, Wisconsin, Camp Nordland in Andover, New Jersey, and Deutschhorst Country Club in Sellersville, Pennsylvania. Camp Siegfried was shut down by the US government when Germany declared war on the United States. It had been protected by the 1st Amendment until that time, when it became illegal for US citizens to swear allegiance to Germany.
A number of Suffolk County facilities are located in Yaphank, including Suffolk County Police Department headquarters, the county fire academy, and the Suffolk County Farm and Education Center, which offers a glimpse into the workings of an authentic 100+ year old farm and educational programs by Cornell Cooperative Extension.
A quarter horse racing facility named Parr Meadows operated in Yaphank in 1977. The racetrack reopened in 1986 for a single meet, then called Suffolk Meadows. In 1979, Parr Meadows served as the venue of a tenth anniversary reunion concert that featured many of the original performers from the Woodstock Festival.