Following the remarkable success of Joshua's initial conquest of Canaan (the "Promised Land"), the Israelites descend into repeating cycles of moral and spiritual decline. The troubles of God's "Chosen People" are the result of disobeying God, disobeying leaders, idolatry, religious apathy, and intermarriage with wicked Canaanites who didn't share the Israelite's religious beliefs. In response to Israel's spiritual apathy and religious apostasy, God gave the Israelites over to be oppressed by their regional neighbors.
The cycle of decline includes: 1) God's people depart from God, 2) God allows Israel's neighbors to oppress them, 3) The Israelites return to God and plead for Him to save them, and 4) God raises-up Judges (often military leaders) to deliver the Israelites from their enemies. This cycle is repeated numerous times, and God's Judges are often portrayed as flawed leaders who vacillate between acts of faithful righteousness and terrible acts of sin...much like the rest of Israel.
In contrast to the flawed Israelite community, God is portrayed as an incredibly merciful creator who time-and-again forgives His Chosen People for their sinful ways and saves them from their oppressors. To be sure, the events in Judges over 3500 years ago bare a striking resemblance to today's corrupt and religiously apathetic society which desperately needs to repent and return to God.