Demographic history of Montenegro
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Serbia and Montenegro 

This article presents the demographic history of Montenegro through census results.
Contents 
1909
The 1909 census was undertaken by the independent Principality of Montenegro. Ethnicity was decided according to the mother tongue, the official then being the Serbian language.
Total: 317,856 inhabitants Orthodox Christians: 94.38% Serbs: about 95% others mostly Albanians
Today it is considered that the total population was overestimated for political reasons and that it was at about 220,000.
1921
In 1918 Montenegro entered the Kingdom of Serbs, Croats and Slovenes (Yugoslavia). In 1921 it organised a census which recorded the mother tongue and religion. A category called Serbian or Croatian was to include all respondents who termed their mother tongue as Serbian. In the counties Andrijevica, Bar, Kolasin, Niksic, Podgorica and Cetinje, which are categorized in official statistics as Montenegro, there were:
Total: 199,227 inhabitants Serbian or Croatian: 181,989 or 91.35% Albanian: 16,838 or 8.45%
The counties Berane and Bijelo Polje, which are today in Montenegro, were considered counties of Old Serbia:
Berane, total 23,864 inhabitants, Serbian or Croatian 23,561 or 98.73% Bijelo Polje, total 26,147 inhabitants, Serbian or Croatian 26,136 or 99.96%
Summed results:
Total: 249,238 inhabitants Serbian or Croatian: 231,686 or 92.96% others mostly of Albanian language
1931
The 1931 census was also taken by the Kingdom of Yugoslavia but was later processed in Communist Yugoslavia. Results within today's borders of Montenegro were:
Total: 360,044 inhabitants Orthodox: 272,702 or 80.88% Roman Catholics: 26,070 or 7.24% Muslims 61,038 or 16.96% Serbian or Croatian language: 339,955 or 90.13% Albanian language: 18,098 or 5.03%
1948
In 1945, after WWII, Communist Yugoslavia was formed, and Montenegro was proclaimed as one of its constituent republics. The 1948 and following censa were taken by the Republic of Montenegro.
Total: 377,189 inhabitants Serbs: 6,707 or 1.78% Montenegrins: 342,009 or 90.67% Albanians: 19,425 or 5.15% Croats: 6,808 or 1.8%
Practically all people who have in former censa declared themselves as having Serbian mother tongue were now declared as Montenegrins.
1953
The 1953 census results:
Total: 419,873 inhabitants Serbs: 13,864 or 3.3% Montenegrins: 363,686 or 86.62% Croats: 9,814 or 2.34% Yugoslavs: 6,424 or 1.53% Albanians: 23,460 or 5.58%
This census witnesses the forming of the Yugoslav nation.
1961
The 1961 census results:
Total: 471,894 inhabitants Serbs: 14,087 or 2.99% Montenegrins: 383,988 or 81.37% Muslims: 30,665 or 6.5% Croats: 10,664 or 2.26% Yugoslavs: 1,559 or 0.33% Albanians: 25,803 or 5.47%
In 1968 the Communist Yugoslav government introduced a new category, Muslims by nationality.
1971
The 1971 census results:
Total 529,604 inhabitants Serbs: 39,512 or 7.46% Montenegrins: 355,632 or 67.15% Muslims: 70,236 or 13.26% Croats: 9,192 or 1.74% Yugoslavs: 10,943 or 2.07% Albanians: 35,671 or 6.74%
1981
The 1981 census results:
Total: 584,310 inhabitants Serbs: 19,407 or 3.32% Montenegrins: 400,488 or 68.54% Muslims: 78,080 or 13.36% Croats: 6,904 or 1.81% Yugoslavs: 33,146 or 5.67% Albanians: 37,735 or 6.46%
1991
The 1991 census results:
Total: 615,035 inhabitants Serbs: 57,453 or 9.34% Montenegrins: 380,467 or 61.86% Muslims: 89,614 or 14.57% Croats: 6,244 or 1.02% Yugoslavs: 26,159 or 4.25% Albanians: 40,415 or 6.57%
2003
Montenegro_ethnic.jpg
The 2003 census was undertaken by Montenegro, which now, together with Serbia, constitutes Serbia and Montenegro.
Total: 672,656 inhabitants Serbs: 201,892 or 30.01% Montenegrins: 273,366 or 40.64% Bosniaks: 63,272 or 9.41% Muslims: 28,714 or 4.27% Croats: 7,062 or 1.05% Albanians: 47,682 or 7.09%
This census witnessed the forming of the Bosniak nation; quite a few people still thought of themselves Muslims by nationality, however. Also, there are very few people left who consider themselves Yugoslavs. But the biggest difference with previous censa is the unparalleled increase in the number of Serbs.
Source
 Montenegrin Census' from 1909 to 2003 (http://www.njegos.org/census/index.htm)