Gradius/Life Force question.

In Games

I thought Gradius 1 in the U.S. was called Life Force. However, I just picked up a copy of Gradius 1 for the NES called......Gradius. Is there anyone who can sort this out? Thanks in advance.

This might help some, but I'm sure there are better sites on the topic. This was my first search:

here Life Force is Gradius 2.

I believe the 'Gradius' series originally stemmed from Konami's earlier 'Nemesis' series of shooters.

There were three 'Nemesis' games (that I know of) and currently five 'Gradius' games (I think).

'Life Force' is a port of 'Salamander', which are both hybrids of 'Gradius'.

Somehow 'Life Force' is also the first game in the 'Thunder Force' series.

There is also a 'Gradius/Nemesis' spin-off series of shooters called 'Parodius'.

And of course, I base all of this information on purely nothing.

Oh well, I found a website but haven't bothered to read it yet.