Why did Congress rebel at the Reconstruction Plan put forth by President Johnson

Many Republicans were angry because they wanted protection for the freed slaves. Confederates had returned to power in several states and those leaders wanted to deny them their rights as free people.

Explanation:

At the beginning, many Northerners believed Johnson's plan deserved a chance to succeed. However, the way the southern states were doing, they turned most of the North against the policy. The new legislatures passed the Black Codes which limited the former slaves' legal rights and economic options.

could you go a bit more in depth with you question? it's quite hard to understand. as soon as you do that i will be glad to : )