One can find out all they need to know about Barclays International Banking on their website - Barclays. Barclays operates in 50 countries and has a worldwide operation with 140,000 employees. Go online to Barclays and find your local contact with Barclays.
Barclays bank is a privately owned bank. It is owned by Barclays Group Plc. and not by any country. If you are asking about the country in which the owners of Barclays bank are, then the answer is England. Barclays bank was created in England with headquarters in Canary Wharf, London, England.