My eldest brother has taken a life insurance policy on my mother, probably unknowingly to her? When she does eventually go would I or my other brother be able to claim any of the life insurance proceeds that he has taken out on my mother?

No, he bought and paid for it, then he is the sole beneficiary if he so desires... because if you want to buy your own policy on her and pay the premiums... then you can have your own too that he won't get any part of.

No, like Smoothy said, he bought it and paid for it, that means he's the sole beneficiary unless he lists others. You cannot get a part of that policy once your mother passes.

Think of it this way. You have a car, you pay insurance on that car. You're in an accident. Would your brother be awarded part of the payout? Of course not, because it's your policy, you paid for it.

You can take out a policy of your own, and pay for it, and list yourself as the beneficiary. Also, any policy your mother took out would likely list all of her children as beneficiaries, that's something you'd have to ask her. But the policy your brother paid for is his.