Which law to apply to divorce in Spain? Foreign Laws to Divorce Proceedings in Spain
Spanish Law allows application of foreign laws to divorce proceedings, but under strict rules: which law to apply to divorce in Spain?

A British national was married to a British woman, with the couple having children below the age of majority. They had been living in Fuerteventura for the last 10 years.
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The husband wished to initiate judicial divorce proceedings in order to obtain custody of the children and wanted to know which law would apply to the divorce – would it be Spanish on the basis that they were resident here, or English on the basis that they had married there and with English being their nationality?
Which law to apply to divorce in Spain?
It is correct to say that the Spanish Civil code establishes that the applicable law in a separation or divorce is determined by the nationality of both spouses.
Validity and Content of Foreign Laws
Foreign (ie non-Spanish) laws, in this case English law, in order to be applied to a particular process, must have both validity and content proven to the satisfaction of the Court; any reliance upon English law in Spanish proceedings, being as it is, a question of fact, must like any other fact be alleged and proven, it being necessary to confirm the exact source of the prevailing law as well as it’s reach and authorised interpretation, such that it’s application does not cause the least reasonable doubt by the Spanish Courts.
All of this must be demonstrated with irrefutable documentation, it not being sufficient to quote foreign legislation, but rather it is necessary to prove the existence and meaning of the law that is being relied upon, normally through rulings and of specialists in the law.
As a result, in the case of the British couple, it was possible for the husband to rely on Spanish law, since English law was not accredited by the other party in the manner that previously we have described as necessary.