1) Private international law governs issues related to marriage such as validity, dissolution, and inheritance across legal jurisdictions.
2) Generally, the law of the place where the marriage was solemnized (lex loci celebrationis) determines the formal validity of the marriage. However, some countries also consider the law of the domicile (lex domicilii).
3) In India, Hindu and Muslim marital laws have different requirements for a valid marriage. Under Hindu law, saptapadi is essential while Muslim law treats marriage as a civil contract requiring an agreement with witnesses.