Norway has an interesting history in that it has been united with other countries for most of its existence and therefore has been ruled by monarchs of other countries. Only from 872-1262 and from 1905 to the present has there been an actual Kingdom of Norway. Olav IV Haakonsson, born in 1370, was the last Norwegian king to be born in Norway until the birth of the present king, Harald V in 1937. During the years of the Norwegian Kingdom (872-1261), the succession to the throne was not clear-cut and often resulted in conflict. As a result, brothers would frequently share the throne.
For more information see:
List of Norwegian Monarchs
History from the official website of the Norwegian monarchy
Timeline of the Kingdoms
The Norwegian Kingdom: 872- 1262
The Union with Iceland and Greenland: 1262-1814
The Union of Sweden and Norway: 1319-1343
The Union of Denmark and Norway: 1380-1396
The United Kingdoms of Denmark, Norway, and Sweden: 1397-1523
The United Kingdoms of Denmark and Norway: 1523-1536
The Kingdom of Denmark-Norway: 1536-1814
The Union of Sweden and Norway: 1814-1905
The Kingdom of Norway: 1905-present
Monarchs of the Norwegian Kingdom
Harald I Fairhair, son of Halfdan the Black: 872-933
Eirik Bloodaxe, son of Harald I Fairhair: 930-934
Haakon I the Good, son of Harald I Fairhair: 934-961
Harald II Gråfell, son of Eirik Bloodaxe: 961-976
Haakon Jarl, son of Sigurd Haakonsson: 976-995
Olav I Tryggvason, great grandson son of Harald I Fairhair: 995-1000
Svein Forkbeard, son of Harald I of Denmark: 999-1015
Olav II Haraldsson, (Saint Olav) son of Harlad Grenske: 1015-1028
Knut the Great, son of Svein Forkbeard: 1028-1035
Magnus I the Good, son of Saint Olav: 1035-1047
Harald III Haardraade, son of Sigurd: 1046-1066
Magnus II Haraldsson, son of Harald III Haardraade: 1066-1069
Olav III Kyrre, son of Harald III Haardraade: 1067-1093
Haakon Magnusson, son of Magnus II Haraldsson: 1093-1094
Magnus III Barefoot, son of Olav III Kyrre: 1093-1103
Olav Magnusson, son of Magnus III Barefoot: 1103-1110
Øystein I Magnusson, son of Magnus III Barefoot: 1103-1123
Sigurd I Jorsalfar, son of Magnus III Barefoot: 1103-1130
Magnus IV the Blind, son of Sigurd I Jorsalfar: 1130-1135
Harald IV Gille, son of Magnus III Barefoot: 1130-1136
Sigurd Munn, son of Harald IV Gille: 1136-1155
Øystein II Haraldsson, son of Harald IV Gille: 1136-1157
Inge Krokrygg, son of son of Harald IV Gille: 1136-1161
Haakon II Herdebrei, son of Sigurd Munn: 1157-1162
Magnus V Erlingsson, grandson of Sigurd I Jorsalfar: 1161-1184
Sverre Sigurdsson, son of Sigurd Munn: 1177-1202
Haakon III Sverresson, son of Sverre Sigurdsson: 1202-1204
Guttorm Sigurdsson, son of Sigurd Munn: 1204-1204
Inge Baardsson: 1204-1217
Erling Steinvegg: 1204-1217
Filippus Simonsson: 1207-1217
Haakon IV Haakonsson, son of Haakon III Sverresson: 1217-1263
MagnusVI Lagabøte, son of Haakon IV Haakonsson: 1263-1280
Eirik II Magnusson, son of MagnusVI Lagabøte: 1280-1299
Haakon V Magnusson, son of Magnus VI Lagabøte: 1299-1319
Monarch of the Union of Sweden and Norway
Magnus VII Eriksson, grandson of Haakon V Magnusson: 1319-1343
Monarch of the Norwegian Kingdom
Haakon VI Magnusson, son of Magnus VII Eriksson: 1343-1380
Monarch of the Union of Denmark and Norway
Olav IV Haakonsson, son of Haakon VI Magnusson: 1380-1387
Monarchs of the United Kingdoms of Denmark, Norway, and Sweden
Margrethe I, wife of Olav IV Haakonsson: 1387-1389
Eric VII of Pomerania, adopted by Margrethe I: 1389-1442
Christoffer III, nephew of Eric VII of Pomerania: 1442-1448
Karl I Knutsson, son of Knut Bonde: 1449-1450
Christian I, son of Count Dietrich of Oldenburg: 1450-1481
Hans, son of Christian I: 1481-1513
Christian II, son of Hans: 1513-1523
Monarch of the United Kingdoms of Denmark and Norway
Frederik I, son of Christian II: 1523-1533
Monarchs of the Kingdom of Denmark-Norway
Christian III, son of Frederik I: 1534-1559
Frederik II, son of Christian III: 1559-1588
Christian IV, son of Frederik II: 1588-1648
Frederik III, son of Christian IV: 1648-1670
Christian V, son of Frederik III: 1670-1699
Frederik IV, son of Christian V: 1699-1730
Christian VI, son of Frederik IV: 1730-1746
Frederik V, son of Christian VI: 1746-1766
Christian VII, son of Frederik V: 1766-1808
Frederik VI, son of Christian VII: 1808-1814
Christian VIII Frederik, grandson of Frederik VI: 1814-1814
Monarchs of the Union of Sweden and Norway
Carl II, son of King Adolf Frederik of Sweden: 1814-1818
Carl III Johan, son of Henri Bernadotte: 1818-1844
Oscar I, son of Carl III Johan: 1844-1859
Carl IV, son of Oscar I: 1859-1872
Oscar II, son of Oscar I: 1872-1905
Monarchs of the Kingdom of Norway
Haakon VII, son of King Frederik VII of Denmark: 1905-1957
Olav V, son of Haakon VII: 1957-1991
Harald V, son of Olav V: 1991-present