from ~1700s: 300 years of back and forth skirmishes, full on wars, deportation of entire Chechen nation in 1944 killing like 1/4.
~1970s(when people were allowed to return to Chechnya)-1990s: communism, peace, poverty but education and just like any other Soviet republic
1992: breakup of USSR, Chechnya declared independence
Nov 1994: First Chechen-Russian War errupted. Things weren't going well for Russia economically and then-Russian-president Yeltsin decided to attack the capital of Chechnya and bring it back under control. Everybody thought it would be over in a matter of days but it wasn't and spread to other regions of the Chechen republic. The Chechen resistance up to this point was largely nationalistic and consisted of different tribes and Islam didn't play as big of a role. Comparable to FSA. Chechens eventually won the war by holding a hospital hostage and forcing the Russian troops to retreat.
Aug 96 - 1998: "peace" aka surreal shariah-tribal-war-mafia-state
1999-2000 Second Chechen War. By now there had been an influx of foreign fighters. You'd find Arabic spoken on the streets sometimes which didn't happen before. And Salafism had come from Dagestan by means of, among others, Imam al Khattab. People just loved him. So him and Basaev decided to attack neighbouring Dagestan and that's when Russia said we've had enough and went all in this time around and cracked down hard.
2002-2006: minor raids, insurgencies, skirmishes, some isolated bombings of rebel locations, suicide attacks but already rebuilding
estimated casualties from 1994-2004 ~200,000 (out of 1 million people)