The colony of Louisiana was founded in 1699 by two brothers, Pierre Le Moyne d'Iberville and Jean Baptiste Le Moyne de Bienville. Its boundaries stretched as far east as the Perdido River, about halfway between present-day Mobile, Alabama, and Pensacola, Florida. It stretched westward to the Red and Calcasieu rivers, next door to Spanish territory, and it extended north all the way to Canada—which was a French possession. The vast boundaries of colonial Louisiana included part or all of at least ten states: Alabama (western part), Arkansas, Illinois, Kentucky, Louisiana (eastern part), Minnesota, Mississippi, Missouri, Oklahoma, and Tennessee.

France reigned over the Louisiana colony from 1699 until she lost all her North America holdings in 1763, at the end of the Seven Years' War. Great Britain claimed all French territory east of the Mississippi River, and all French territory west of the Mississippi went to Spain.

There is one quirk in this division important to the genealogist: New Orleans, built on the east bank of the Mississippi River, should have gone to Great Britain but went to Spain instead. In 1763 the kings of France and Spain were cousins. They connived together to keep New Orleans out of the hands of Great Britain, their common enemy. They obtained their victory by convincing the British negotiators that New Orleans was actually on the west bank and not the east.

The Spanish ruled Louisiana from 1763 until they gave it back to France in 1800. It is important to note that although Louisiana was once again a French possession, there was no change of affairs. Spanish officials continued to govern the colony while Napoleon secretly negotiated with Thomas Jefferson to sell Louisiana to the United States. Therefore, if an ancestor lived in colonial Louisiana between 1800 and 1803 search for him or her in the Spanish records, not the French.

For nearly 300 years Louisiana was one of the areas in the world most sought after by the three major powers of Europe: Spain, France, and Great Britain. Spain explored it first but withdrew in favor of richer lands farther south. Then France settled the land, but its decaying monarchy had little regard for the colony, while it was obvious that the French statesmen who were interested had never dealt with the vast fields upon which their policies were to operate. They did not comprehend the great extent of the country, and were entirely ignorant of the means necessary for the successful cultivation of their lower Mississippi colony. Once the Spanish secured the colony they were doing a magnificent job of building it when they were forced by Napoleon to relinquish control.

The struggle for Louisiana was finally won, not by one of the European nations which had plotted and fought for its permanent control for so long, but by the infant nation which had arisen on the eastern shores of North America. The United States took possession of Louisiana in December 1803 and began preparing the colony, which had never known a working democracy, for statehood. War broke out between England and the United States in 1812, and Great Britain began to plan the conquest of Louisiana, which failed when the Battle of New Orleans was lost. Less than four months later Louisiana celebrated its third anniversary as an American state.