Q:

Is there any scientist whose work was not recognised during his/her lifetime and was underestimated?

A lot of people have contributed to the development of science (which includes mathematics). I have read that Newton's popularity was powerful enough to dominate the wave-model. Similarly, do we have any scientist whose work was underestimated, was not accepted by the community and was left unnoticed during his/her lifetime, but when a popular scientist published the same thing, got a wide appreciation?

A:

Julius Robert Mayer is now known for enunciating in 1841 one of the original statements of the conservation of energy (First Law of Thermodynamics). But his achievements were overlooked, and priority for the discovery of the mechanical equivalence of heat was attributed to James Joule. According to Wikipedia:

He attempted suicide on 18 May 1850 and was committed to a mental institution. After he was released, he was a broken man and only timidly re-entered public life in 1860. However, in the meantime, his scientific fame had grown, and he received a late appreciation of his achievement, although perhaps at a stage where he was no longer able to enjoy it.

A:

George Green springs to mind. Whilst he had a very interesting, and not unsuccessful life, it was only after his death and Lord Kelvin looking through his works on mathematical physics that he was appreciated for quite how significant he truly was. 

A:

I can think of

Alfred Wegener, the discoverer of plate tectonics, who died completely ignored before his theory gained acceptance.

Ludwig Boltzmann, defender of statistical mechanics in Physics.

Giordano Bruno, who was burnt at the stake for defending that the Universe is infinite and not centered around the Earth.

Galileo Galilei, who was kept under house arrest for the same reason.

Gregor Mendel, discoverer of the laws of genetic inheritance, who died completely unknown.

