The islands of St. Thomas, St. Croix and St. John constituted a Danish colony from 1754 until 1917, when the US bought them from Denmark. The LDS has microfilmed a number of church records of various denominations there, although some are written in Danish, French, Latin. Some examples are given below. Check familysearch.org for the film numbers.

19 reels of baptisms, confirmations, marriages and burials in the Catholic records of the Cathedral Church of Sts. Peter & Paul, 1778-1970.

13 reels of parishoner & minister lists, deaths, christenings, confirmations, first communions, and marriages, and the Refuge Society of the Frederick Evangelical Lutheran Church, 1739-1974.

7 reels of baptismal registers, confirmation, marriages, marriage banns, and deaths for the All Saints Episcopal Church, 1785-1979.

Additional films said to be available at the LDS (but not listed in the LDS catalog) are also listed at www.candoo.com/gensources/churches.htm#cc

Keep in mind that the Moravians sent missionaries there in the 18th Century to convert the slaves to Christianity as well. There are many original records of christenings and other slave records at their headquarters in Bethlehem, PA!

Good luck !