What was the first organism ever cloned successfully and in what year?

1952
First cloning experiment with frogs
Robert Briggs and T.J.King used a pipette to suck the nucleus from the
cell of an advanced frog embryo and added it to a frog egg. It did not
develop.

1970
Another experiment on frogs yields better results
John Gurdon tried the same procedure. The eggs developed into tadpoles
but died after they were ready to begin feeding. He later showed that
transplanted nuclei reverted to an embryonic state.