1. Did your brother leave a will, or did he die without making a will? Was the will made in America or in the UK?
2. Succession to an estate where there are movables and potentially immoveables, given his business, is governed by the law of the domicile of the deceased. Here, that would be the state of Alaska. In strict point of law, you should take out letters of administration in Alaska where he had his domicile at the time of his death. Whilst it could be argued that your brother still had his domicile of origin in the UK, that is not going to greatly assist in the practical administration of the estate because you are going to have to get any probate extracted in England recognised in Alaska. So, I would suggest you simply take out letters of administration or probate in Alaska and work from there.
3. I would also suggest that as part of any probate in Alaska, you seek an account, formally of the business which your brother had with his fellow employee. If there was a partnership, then in strict point of law, this should be wound up and the assets divided. So, you should consider how best to do this in Alaska.
4. Be aware that the concept of domicile is a fluid one. So, if you are not happy with probate in Alaska, you can seek to take out letters of administration in the UK based on your brother never losing his domicile of origin in the UK. This has the advantage that you will know the law and understand how it applies. However, be aware that there are usually practical problems as you then have to get that Grant of Probate recognised in Alaska. It is generally necessary to once again apply for probate in Alaska.
5. Please Accept or Rate the Answer Kevin, as unless you do so, your Expert will not receive payment for answering your question.