Kitto's Popular Cyclopedia of Biblial Literature
Bithyn′ia, a province of Asia Minor, on the Euxine Sea and the Propontis; bounded on the west by Mysia, on the south and east by Phrygia and Galatia, and on the east by Paphlagonia. The Bithynians were a rude and uncivilized people, Thracians who had colonized this part of Asia, and occupied no towns, but lived in villages. That Christian congregations were formed at an early period in Bithynia, is evident from the Apostle Peter having addressed the first of his Epistles to them (1 Peter 1:1). The Apostle Paul was at one time inclined to go into Bithynia with his assistants Silas and Timothy, 'but the Spirit suffered him not' (Acts 16:7).
Kitto, John, ed. Entry for 'Bithynia'. "Kitto's Popular Cyclopedia of Biblial Literature". https://www.studylight.org/encyclopedias/eng/kbe/b/bithynia.html.