All 12 Uses

however
in
Incidents in the Life of a Slave Girl
(Auto-generated)

It did not, however, prohibit him from retaining the silver candelabra, which had been purchased with that money.†
Chpt 2 *

however = a word used to connect contrasting ideas as when using though, in spite of that, in contrast, nevertheless, etc.
However that might be, I was determined that I would never go to Louisiana with him.†
Chpt 7 *

however = in whatever way
The poor fellow had, however, made up a story, which augmented his own sufferings and those of the colored people.†
Chpt 12

however = a word used to connect contrasting ideas as when using though, in spite of that, in contrast, nevertheless, etc.
That, however, was a slight trouble, compared with the fear that their pecuniary embarrassments might induce them to sell my precious young daughter.†
Chpt 33
However, he afterwards relented in some degree.†
Chpt 4
A clergyman who goes to the south, for the first time, has usually some feeling, however vague, that slavery is wrong.†
Chpt 13
She had enough to be independent; and that is more than can ever be gained from charity, however lavish it may be.†
Chpt 16
However, I don't blame William.†
Chpt 26
However, I said nothing.†
Chpt 35
However, I resolved to try the experiment.†
Chpt 40
I do not sit with my children in a home of my own, I still long for a hearthstone of my own, however humble.†
Chpt 41
But, however it may be regarded by the incredulous, I know that it is full of living truths.†
Chpt Appe

Definitions:

(1) (however as in: However, complications may...)
though (or another expression that connects contrasting ideas)

Based on idea 1 we might not expect idea 2, but this is a way of saying that even though idea 1 exists, we still have idea 2. Synonyms include in spite of that, despite that, nevertheless, nonetheless, on the other hand, in contrast and but.
(2) (however as in: However much she tried...)
to whatever degree (regardless of how much; or whatever unspecified amount)
(3) (however as in: However you do it, get it done!)
in whatever way
(4) (meaning too rare to warrant focus)
Much more rarely (and arguably incorrectly), however can be used to intensify the word how, as when one says "However did you find her?" Grammarians would suggest using two words for that usage: "How ever did you find her?"