Summary: There are many good studies and observations about the seven churches from a spiritual perspective that can be applied to churches today. However, this study will not address them, but rather review the history of the churches and where they are today (2021).
In the Book of Revelation, Jesus sent a message to seven churches that were located in the western part of Asia Minor, directly south of the Black Sea. The word "church" is translated from the Greek word "ekklesia" which means the people of God, the whole collective body of Born-Again Christians found everywhere on the Earth throughout history.
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A. The Seven Churches
1 "To the angel of the church in Ephesus write: 'The words of him who holds the seven stars in his right hand, who walks among the seven golden lampstands. 2 "'I know your works, your toil and your patient endurance, and how you cannot bear with those who are evil, but have tested those who call themselves apostles and are not, and found them to be false. 3 I know you are enduring patiently and bearing up for my name's sake, and you have not grown weary. 4 But I have this against you, that you have abandoned the love you had at first. 5 Remember therefore from where you have fallen; repent, and do the works you did at first. If not, I will come to you and remove your lampstand from its place, unless you repent. 6 Yet this you have: you hate the works of the Nicolaitans*, which I also hate. 7 He who has an ear, let him hear what the Spirit says to the churches. To the one who conquers I will grant to eat of the tree of life, which is in the paradise of God.' (Rev 2:1-7 ESV)
*(The Nicolaitans were Gnostics who wanted to blend Christianity with many pagan practices such as sexual immorality)
Ephesus was a magnificent and influential capital city of Asia Minor on the Aegean Sea. It was the fourth largest city of the Roman Empire in the first Century and was the center of trade and the seat of its government, learning, art, wealth, and religion. The amphitheater could hold up to twenty-five thousand people. It was the home to the Temple of Artemis (aka Diana), and considered one of the seven wonders of the ancient world. Artemis was the goddess of fertility who was believed to control the reproduction of humans, animals, and crops. The city was also known throughout the ancient world for its temple prostitutes and hedonistic celebrations.
On the Apostle Paul's third missionary journey [Acts 18:23], he chose to live there for two to three years. He helped turn the whole province to Jesus [Acts 19:8-12] as he was used by the Holy Spirit to heal the sick and cast out demons, even with "handkerchiefs and aprons" (Acts 19:19).
The Apostle Paul taught daily and debated the great doctrines of the many beliefs found there until "all Asia" had heard the truth of Jesus. He wrote his first letter to the Corinthians (57 A.D.+-) there and then a letter directly to the Ephesians (62 AD+-).
The church at Ephesus had Paul as its founder and Timothy as its first pastor, who ultimately died a victim of mob violence for his protests against the annual festival of Artemis [1 Tim 1:3]. In 69 A.D., John the beloved was the Pastor from 69 A.D. until he was exiled to the prison island of Patmos (95+- A.D.), where he died a natural death (98 A.D. +-).
Ephesus remained the most important city of in Asia. However, in 263 A.D., it was attacked by a group of mercenaries who sacked and nearly destroyed it. Constantine rebuilt it during the 5th and 6th centuries.
The city was attacked again in the year 655 A.D., as well as in 700 and 716 A.D.. It was fully conquered in 1090 A.D, and the inhabitants were either slaughtered or carried away into captivity. Christians took it back in 1100 A.D. and changed the name of the town to Hagios Theologos, and kept control of the region until 1308 A.D. At that point, it became merely a small village called Ayasalouk.
Ultimately the great city of Ephesus literally vanished from the earth, gone with the wind. Today, the area where it once was is now a place of desolation without an inhabitant.
8 "And to the angel of the church in Smyrna write: 'The words of the first and the last, who died and came to life. 9 " 'I know your tribulation and your poverty (but you are rich) and the slander of those who say that they are Jews and are not, but are a synagogue of Satan. 10 Do not fear what you are about to suffer. Behold, the devil is about to throw some of you into prison, that you may be tested, and for ten days you will have tribulation. Be faithful unto death, and I will give you the crown of life. 11 He who has an ear, let him hear what the Spirit says to the churches. The one who conquers will not be hurt by the second death.' (Rev 2:8-11 ESV)