This very interesting surname has been well recorded in the registers of the city of London since at least the time of King James 1st of England and V1 of Scotland. However during that period of over three centuries the spelling has undergone may changes, being at various times found as Crumocke, Crumack, Cromack, which now seems to be the accepted form, Crumack, and Cromek, which looks almost Polish! The origin is uncertain, however it would seem to have been locational. If so it is either Olde English or Gaelic, since the prefix would seem to be from the pre 7th century word "crwm" meaning crooked. The only place in the British Isles which would seem to in anyway fit the description is Crummock Water, a lake in Cumbria, in the far north of England, which may itself have been the site of a now 'lost' medieval village. Locational names are by their nature, 'from' names. That is to say names given to people after they left their original homes and moved elsewhere. As spelling over the years has been at best erratic and local accents very thick, the further a person moved from their original home,often the greater the distortion of the spelling. In this case there is no evidence that the name as a surname, was ever recorded in Cumbria. Early examples of the name spelling include those of Mary Cromacke, who married Oliver Sanders at the church of St Andrews by the Wardrobe, on April 19th 1624, and Dinah Cromack who married Richard Carter at the church of St margaret Moses, on June 28th 1822, both being in the registers of the city of London.