Generally speaking, you will contest a will in whichever state probate is obtained in. While there are exceptions, probate will be obtained in the state that the deceased owned property in or lived in.
Domicile means where the deceased was physically present, where he or she lived.
If a deceased was domiciled in one state but left property in another it is sometimes necessary to obtain a reseal of the grant of probate in another state.
If you are uncertain about which state’s laws apply, feel free to give us a call.