from
Easton's 1897 Bible Dictionary
Bithynia
a province in Asia Minor, to the south of the Euxine and
Propontis. Christian congregations were here formed at an early
time (1 Pet. 1:1). Paul was prevented by the Spirit from
entering this province (Acts 16:7). It is noted in church
history as the province ruled over by Pliny as Roman proconsul,
who was perplexed as to the course he should take with the
numerous Christians brought before his tribunal on account of
their profession of Christianity and their conduct, and wrote to
Trajan, the emperor, for instructions (A.D. 107).