context: Buddhism was introduced in about the mid-third century B.C . , and a great civilization developed at the cities of Anuradhapura ( kingdom from circa 200 B.C . to circa A.D. 1000 ) and Polonnaruwa ( from about 1070 to 1200 ) .
hypothesis: A.D. is a geographical/political entity
corpus-sent-id: p06/d0689 2