Historical clue formulations

• Oslo's home: Abbr. — 2014-03-18
• Land on the Arctic Cir. — 2013-04-21
• Major Eur. oil exporter — 2012-12-14
• Neighbor of Swed. — 2010-03-14
• Swed. butter? — 2005-02-17
• Neighbor of Swed. — 2004-05-28
• Swed. neighbor — 2004-01-04
• Neighbor of Swed. — 2000-03-02