The book of Judges covers about 400 years. There were five periods of servitude where they were controlled by different nations. They were strong and prosperous when they were worshipping God. When they went a whoring after other gods they would be overrun by other nations and oppressed and put into servitude. Israel was free as long as the Judges lived. When they died they would go back into idolatry and consequently into slavery until another Judge rose up to lead them.
After Joshua died Israel served God until the elders died then they served Baal. They had failed to drive out the inhabitants of the land as God had instructed them to do so they became influenced by them and led astray. We are also instructed to not be unequally yoked together with unbelievers. Always guard the Word in our lives.
Throughout Judges there are people who would rise up and believe God and persuade Israel to come back to God. When they listened to him/her and obeyed they lived well and was able to defeat their enemies and get out of servitude. Read chapter 2.
In chapter 4 we read about Deborah a prophetess that Judged Israel. She marshaled an army and went up against the Canaanites that were oppressing them and kicked them out. She was just doing what God had told her to do (Judges 4:6 & 7). Because they believed and obeyed, Israel had rest 40 years. Thus we see a pattern; the next generation didn't believe God and after the prophetess died they returned to the pagan gods.
To be a deliverer in Israel you didn't have to have the most dynamic personality and great oratory prowess. You had to believe God, worship Him and listen! Gideon is a wonderful example of a man who simply believed God.
:1 And the children of Israel did evil in the sight of the LORD:
and the LORD delivered them into the hand of Midian seven years.
:2 And the hand of Midian prevailed against Israel:
and because of the Midianites
the children of Israel made them the dens
which are in the mountains, and caves, and strong holds.
:3 And so it was, when Israel had sown,
that the Midianites came up,
and the Amalekites,
and the children of the east, even they came up against them;
:4 And they encamped against them,
and destroyed the increase of the earth,
till thou come unto Gaza,
and left no sustenance for Israel,
neither sheep, nor ox, nor ass.
:5 For they came up with their cattle and their tents,
and they came as grasshoppers for multitude;
for both they and their camels were without number:
and they entered into the land to destroy it.
:6 And Israel was greatly impoverished because of the Midianites;
and the children of Israel cried unto the LORD
:7 And it came to pass,
when the children of Israel cried unto the LORD because of the Midianites,
:8 That the LORD sent a prophet unto the children of Israel, which said unto them,
Thus saith the LORD God of Israel,
I brought you up from Egypt,
and brought you forth out of the house of bondage;
:9 And I delivered you out of the hand of the Egyptians,
and out of the hand of all that oppressed you,
and drave them out from before you,
and gave you their land;
:10 And I said unto you,
I am the LORD your God;
fear not the gods of the Amorites, in whose land ye dwell:
ye have not obeyed my voice.
:11 And there came an angel of the LORD,
and sat under an oak which was in Ophrah,
that pertained unto Joash the Abiezrite:
and his son Gideon threshed wheat by the winepress,
to hide it from the Midianites.
:12 And the angel of the LORD appeared unto him, and said unto him,
The LORD is with thee, thou mighty man of valour .
Now put yourself in Gideon's shoes (sandals). Gideon is working along threshing his wheat by the winepress (instead of the threshing floor) trying not to be noticed when this guy shows up--just appears--and says, "The Lord is with you, you mighty man of valour." This sort of thing doesn't happen everyday! God's opinion of Gideon is that he is a mighty man of valour, we will see what Gideon's opinion is. After Gideon collects himself he recognizes this is an angel and speaks to him.
:13 And Gideon said unto him,
Oh my Lord, if the LORD be with us,
why then is all this befallen us?
and where be all his miracles which our fathers told us of, saying,
Did not the LORD bring us up from Egypt?
but now the LORD hath forsaken us,
and delivered us into the hands of the Midianites.
:14 And the LORD looked upon him, and said,
Go in this thy might,
and thou shalt save Israel from the hand of the Midianites:
have not I sent thee?
:15 And he [Gideon] said unto him,
Oh my Lord, wherewith shall I save Israel?
behold, my family is poor in Manasseh,
and I am the least in my father's house.
:16 And the LORD said unto him,
Surely I will be with thee,
and thou shalt smite the Midianites as one man.
Gideon didn't think he had the qualifications to help Israel; he was poor and the youngest of his household, typically not the leader. But God looked elsewhere, Gideon had the heart and he believed in the one true God, he didn't worship other gods. Because of Gideon's faith God could talk to him and God knew Gideon's heart as He does our own, He knew Gideon would believe and become a mighty man of valour.
:17 And he [Gideon] said unto him,
If now I have found grace in thy sight,
then shew me a sign that thou talkest with me.
Gideon asks for a sign so he can believe without a shadow of a doubt. God sends an angel which Gideon serves food to (Oriental custom) and the angel ignites it (sacrifice).
:21 Then the angel of the LORD put forth the end of the staff that was in his hand,
and touched the flesh
and the unleavened cakes;
and there rose up fire out of the rock,
and consumed the flesh
and the unleavened cakes.
Then the angel of the LORD departed out of his sight.
:22 And when Gideon perceived that he was an angel of the LORD, Gideon said,
Alas, O Lord GOD!
for because I have seen an angel of the LORD face to face.
:23 And the LORD said unto him,
Peace be unto thee;
thou shalt not die.
:24 Then Gideon built an altar there unto the LORD,
and called it Jehovahshalom:
unto this day it is yet in Ophrah of the Abiezrites.
[Jehovahshalom: that is, The LORD is our peace]
We will see in the next few chapters how Gideon takes a stand for God and God is with him all the way. Gideon wasn't some famous person and great TV personality born into money and stature. He was the youngest of his family which was poor and oppressed by the Mideanites. Yet, he believed God and that is what made the difference.
I exhort you to read about Israel as they occupy Canaan (chapters 1 & 2), Othniel, Caleb's younger brother (chapter 3), and Deborah the Prophetess in chapters 4 and 5.