||Until recently the severe decline in the populations of many species of grassland birds in eastern North America has aroused relatively little concern or conservation action. This response appears to be rooted in the perception that grassland birds invaded the East Coast from western grasslands after European settlers cleared the forest. Detailed historical accounts and analysis of pollen deposits, however, show that open grasslands existed on the East Coast of North America at the time of European settlement. Extensive grasslands resulted from burning and agricultural clearing by Native Americans. Natural disturbances, such as wildfire and beaver (Castor canadensis) activity, produced grasslands even before Native Americans cleared the forest. The presence of specialized grassland birds in Pleistocene deposits and in the earliest ornithological collections from eastern North America, and the existence of distinctive eastern populations of the Greater Prairie-Chicken (Tympanuchus cupido), Henslows Sparrow (Ammodramus henslowii), and Savannah Sparrow (Passerculus sandwichensis), indicate that grassland birds are an ancient component of biological diversity on the heavily forested East Coast of North America.