“‘This is what the Lord, the God of Israel, says, ‘Let my people go, so that they may hold a festival to me in the desert’”. 

Ex 5:1 NIV 

There are different levels at which events may happen. One level is the historical (what actually happened?) Another is the personal level (who was involved?) Another aspect is the economical (how much did it cost? And what effects did it have on the economy?) Then there is the question of results (What effects did it have?) The theological level is another way of looking at it as well (what role did God play?) 
The approach of Moses and Aaron was not to plead with or to request the Pharaoh to kindly release the Israelites from their four-centuries-long servitude. They presented him with the Lord God’s demands. There was no bargain, no negotiating, no “iffing and butting”. For ancient people the strength of a nation reflected the power of that nation’s god. So whilst to Moses and Aaron “the Lord God” was a supreme God, to the Pharaoh he would be a “nothing god”. The only god other than those of Egypt, whom Pharaoh might even acknowledge would be those of other more powerful nations. In fact, eventually Pharaoh did let them go, and it was quite some “festival” to the Lord that they held in the desert. It lasted for forty years. 
This demand has been echoed by many leaders down the intervening centuries where groups, classes, or nations of people have been enslaved. The example of Israel has served as a model to others. And it has given them hope and motivation. And people in any kind of spiritual slavery look to Christ to deliver and set them free as well. 

Lord, release me from bondage to sin and addictions.