[4] In the period from 2013 to 2021, the Croatian Wikipedia was caught in the spotlight for promoting far-right ideas, including anti-LGBT propaganda and bias against Serbs of Croatia by Holocaust revisionism, particularly negating or whitewashing the atrocities of the Ustaše regime.

According to Jurica Pavičić, a professor at the University of Split and Jutarnji list columnist, the gradual takeover of the Croatian Wikipedia was started in 2009 by "a small group of conservative administrators" who blocked editors for having "liberal-to-moderate views on controversial topics".

[22][8] Reported examples of bias include historical negationism such as watering-down and denial of the crimes committed by the Ustashe regime, and equating anti-fascism with forms of totalitarianism.

[26] The issue was reported by Croatia's daily Jutarnji list and even made its print edition's front page on 11 September 2013.

[29] In 2013, in an interview given to Index.hr, Robert Kurelić, a professor of history at the Juraj Dobrila University of Pula, commented that "the Croatian Wikipedia is only a tool used by its administrators to promote their own political agendas, giving false and distorted facts".

Kurelić further advised,[11] that it would be good if a larger number of people got engaged and started writing on Wikipedia [...] administrators want to exploit high-school and university students, the most common users of Wikipedia, to change their opinions and attitudes, which presents a serious issue.Also in 2013, Snježana Koren, a historian at the Faculty of Humanities and Social Sciences, University of Zagreb, judged the disputed articles as "biased and malicious, partly even illiterate", in an interview with Croatian news agency HINA.

[30] She further added that "These are the types of articles you can find on the pages of fringe organizations and movements, but there should be no place for that on Wikipedia", expressing doubts on the ability of its authors to distinguish good from evil.

[30] The Croatian Wikipedia page on the Jasenovac concentration camp was regarded as a prime example of its historical negationism and distortions.

[5] Hrvoje Klasić, also a historian at the Faculty of Humanities and Social Sciences in Zagreb, stated to the Balkan Investigative Reporting Network in 2018 that "although Jasenovac was in part a labour camp, referring to it as that alone is misleading", arguing that "referring to Jasenovac as simply a collection and labour camp is to use 'the same language' as Ustasa propaganda", and also added that "a number of articles and topics are done in a completely revisionist manner [on the Croatian Wikipedia], with highly emphasised nationalist and, I would dare to say, pro-Ustasa sentiment".

[5][32] In 2021, the Wikimedia Foundation posted a job ad for a disinformation evaluator position, with the aim to further examine disputed content on the Croatian Wikipedia.

It concluded that "A group of Croatian language Wikipedia (Hr.WP) admins held undue de facto control over the project at least from 2011 to 2020.

"[12] According to the assessment, the administrators had abused their power to ban dissidents and selectively enforced and broke rules, resulting in project capture.