Yes, in 2004, but it was struck down by the US Supreme Court on June 26, 2015. The amendment used to say:
(a) This state shall recognize as marriage only the union of man and woman. Marriages between persons of the same sex are prohibited in this state.
(b) No union between persons of the same sex shall be recognized by this state as entitled to the benefits of marriage. This state shall not give effect to any public act, record, or judicial proceeding of any other state or jurisdiction respecting a relationship between persons of the same sex that is treated as a marriage under the laws of such other state or jurisdiction. The courts of this state shall have no jurisdiction to grant a divorce or separate maintenance with respect to any such relationship or otherwise to consider or rule on any of the parties' respective rights arising as a result of or in connection with such relationship.
No. In 2006, the Constitution of Latvia was amended to explicitly prohibit same-sex marriage.
No. No such amendment has been made.
No. No such amendment has been made.
No. No such amendment has been made.
No. No such amendment has been made.
No. No such amendment has been made.
No. No such amendment has been made.
No, not exactly. In 1998, the state constitution was amended to permit the legislature to ban (or, presumably, not ban) same-sex marriage. The legislature afterwards banned it. The amendment says:The legislature shall have the power to reserve marriage to opposite-sex couples.
No. No such amendment has been made. On November 6, 2012, the electorate of Minnesota voted NOT to amend the state constitution to ban same-sex marriage.
No. No such amendment has been made. Same-sex marriage was legalized in Iowa beginning April 3, 2009.
No. No such amendment has been made. In fact, same-sex marriage was legalized in Maine on November 6, 2012.
No. No such amendment has been made. Same-sex marriage was legalized in Washington state on November 6, 2012.