Bernard Ratzer (aka Bernhard, aka Ratzen) (fl. 1756 - 1777) was an important British engineer, cartographer, and surveyor active in the mid to late 18th century. Ratzer served with fellow surveyor Samuel Holland as a lieutenant in military engineers division of the 60th 'Royal American Regiment' during the French and Indian War. Most of his earliest survey work survives only in manuscript form, and is related to the activities of the Royal Americans. Ratzer's first recorded map, created when he was an ensign, details Maine's Passamaquoddy Bay (1756). He also completed several smaller surveys of French and Indian War Forts around Lake Ontario and on the Niagara River. After the war, Ratzer was one of the 1500 victorious British troops that arrived in New York. There New York Governor Henry Moore assigned him the task of improving upon the critically flawed John Montresor map of 1767. This resulted in Ratzer's two most important maps, the 'Ratzen Plan' (1767) and the much larger 'Ratzer Map' (1776), both considered to be among the finest maps of any American city issued during the 18th century. Between surveying the 'Ratzen Plan' and the larger 'Ratzer Map,' Ratzer was promoted to Captain and assigned to work with Samuel Holland on the New York – New Jersey Border Line Survey producing an important manuscript map in 1769, now in the Harvard University Collections. This survey work was published by William Faden in 1778, during the American Revolutionary War, as 'The Jerseys.' Ratzer is known to have worked with William Faden, Thomas Jefferys, Thomas Kitchin, Samuel Holland and Sauthier, among other important 18th century cartographic figures. Due to the engraver Thomas Kitchin's misspelling of his name on the title of the 1767 Plan of the City of New York, also known as the 'Ratzen Plan,' Ratzer's name is often confused as 'Ratzen.'