It is a common idea in Catholic eschatology that the tribulation occurs in two parts, the lesser tribulation and the greater tribulation. But the length of time between the two, the inter-tribulation period, is a matter of some dispute. Some authors have the time as rather short. My view is that it lasts a few hundred years.
* First part of the tribulation: beginning soon and ending with the three days of darkness in 2040 A.D.
* The inter-tribulation period, from 2040 AD (21st century) to 2430 A.D. (25th century).
* Second part of the tribulation: 2430/31 to 2437. Then Christ returns in 2437 A.D.
During the inter-tribulation period, several kingdoms rise and fall, leading to a situation where the world become divided into ten kingdoms only, each led by one king. This is termed the kingdom of the ten kings, yet each of the ten is separate from the others, and they often act in opposition to one another.
After this kingdom reigns for about a hundred years, the Antichrist becomes one of the ten kings. Then he defeats three of the ten, and thereby gains enough power to force the rest of the kingdoms to submit to his rule.
See my eschatology books for more on this topic.
Ronald L. Conte Jr.