Use of "for one" [closed]
Solution 1:
According to the OED:
for one used to stress that the person named holds the specified view, even if no one else does: I for one am getting a little sick of writing about it.
Solution 2:
Unless it was a rhetorical reply to an earlier query (which the context given by you doesn't disambiguate), by including himself at the top of the dissenters' list, Robin Hood is urging others join him. In effect, Robin Hood is saying:
I can't take this lying down. Who else is with me?
For one is used when there are a number of imponderables which the speaker either can't (or doesn't wish to) enumerate in detail.
There are a number of reasons why we'd be better off seeking forgiveness rather than permission. For one, it is easier.
In this use case, the implication is that there are many more reasons which, if the speaker is dared to, can and will enumerate as required to convince his audience.
Solution 3:
It refers to the position of an individual (or possibly a group), usually sharing the opinion presented. Some people enjoy walking naked in the rain. I, for one, certainly do.