In New Testament times, Asia was a Roman province. It was located just east of the Aegean Sea. The Romans created this province in 133. They did this after Attalus III, the king of Pergamum, left his kingdom to them in his will.
Greek map-makers usually used the name "Asia" to mean the whole eastern continent. But from the second century onward, Romans often called the kings of Pergamum "kings of Asia." Because of this, people slowly began using "Asia" to mean only the peninsula (Asia Minor).
The extent of the province of Asia varied throughout its history. Before the Roman occupation, the term referred to the kingdom of the Seleucid dynasty, which Seleucus I founded in 305–281 BC. This usage is seen in the Apocrypha (1 Maccabees 8:6; 11:13; 12:39; 13:32; 2 Maccabees 3:3) and the works of the early Jewish historian Josephus in his "Antiquities." The Romans took the territory from the Seleucids after the war against Antiochus the Great. As a reward, they gave it to their allies, the Attalids. Attalus III eventually willed it to the Romans.
The boundaries of Roman control were stable only after a big revolt was stopped. The province then included regions like Mysia, Lydia, Caria, and Phrygia. It also included areas near the Aegean Sea, like Aeolis, Ionia, and Troas. The coastal islands, such as Lesbos, Chios, Samos, Rhodes, and Patmos, were part of the province too. This mainland area is now part of modern Turkey.
In 116 BC, the province got bigger and included Greater Phrygia. Its borders were Bithynia to the north, Galatia to the east, Lycia to the south, and the Aegean Sea to the west. But these borders changed over time. In 25 BC, Augustus Caesar expanded Rome's control by adding other parts of Phrygia, Lycaonia, Pisidia, and maybe Pamphylia into a province called Galatia. These borders stayed the same until AD 285. Then, the province became much smaller, and "Asia" referred only to the coastal areas and lower valleys of the Maeander, Cayster, Hermus, and Caicus Rivers.
During Roman rule, Pergamum was the capital of the province. By Augustus's time, the Roman governor had moved to Ephesus.
In the New Testament, "Asia" usually meant the Roman province of that name. Sometimes, it meant the area, and other times, it meant the political region. For example, at the Feast of Pentecost in Jerusalem, there were Jews from "Asia." This included other Roman provinces like Cappadocia, Phrygia, and Pamphylia. (Acts 2:9–10). This suggests that Luke, the writer of Acts, used the term to describe the province originally left to the Romans by Attalus III. Luke used the word again in Acts 6:9, indicating the strength of Jewish communities in Asia Minor and confirming the use of "Asia" in the more narrow sense of the Roman province.
On Paul’s second missionary journey, the Holy Spirit stopped him and Timothy from preaching in Asia (Acts 16:6–8). Here, Luke was probably speaking about the original borders of the province. When Paul returned from Greece, he stopped in Ephesus (Acts 18:19–21). On his third missionary journey, he stayed in Ephesus for more than two years so that from this capital city, "everyone who lived in the province of Asia, Jews and Greeks alike" (Acts 19:10).
Luke talked about Asia again in Acts 19:26–27; 20:4, 16, 18; and 27:2. Paul refers to it several times (Romans 16:5; 1 Corinthians 16:19; 2 Corinthians 1:8; 2 Timothy 1:15). The apostle Peter also used the term (1 Peter 1:1). In the New Testament, the risen Christ was the last to refer to Asia. He instructed the apostle John, who was living in exile on the island of Patmos, to write letters to seven specific churches in Asia (Revelation 1:1–4).
Other cities in this Roman province mentioned in the New Testament include:
Laodicea and Hierapolis (Colossians 4:13)