External relations of Guernsey both islands retain their independence with regards to domestic affairs but internationally, the islands would be regarded as one state. A Guernsey-Jersey double taxation agreement was first signed in 1956. In 1998 Guernsey and Jersey electricity companies formed the Channel Islands Electricity Grid to operate and manage the submarine cables between Europe and the Channel Islands. Guernsey has formed part of the British–Irish Council since it was formed in 1999, as does Jersey. Meetings take place twice a year, in 2004, 2010 and 2014 the meetings have taken place in Guernsey. Its stated aim is to "promote the harmonious and
Maritime history of the Channel Islands promise they would be fed and clothed. Jean Martell from Jersey established in 1715 the Cognac manufacturer Martell and established trading links with Guernsey. The Islands had an involvement in the slavery trade. Guernsey has identified 11 sailings, mainly from the Gambia, between 1741 and 1761, with 2,118 slaves taken and 1,800 delivered. The wine trade was very important, in 1771 Guernsey merchant, Le Marchant recorded 8,000 tons of claret shipped from Bordeaux to Ireland, noting it was usual to mix with ¼ of Spanish wines to make it suitable for the Irish market. By controlling the brandy trade from