This work was first published in Hungary more than 70 years ago, and the identity of the author cannot be determined. According to the Hungariancopyright act of 1999 31. § (3): In the event the person of the author is unknown, the term of protection shall be seventy years and shall be counted from the first day of the year following the first disclosure of the work. For explanation of PD status in the US see the template description page.
Important: "the author is unknown" is NOT the same as "I don't know who the author is". You have to provide a reason why you think no one else can know it; otherwise the image shall be deleted.
This license is not applicable for unpublished works; those are protected for 120 years from creation in the US. It is also not applicable for works that have been published in Hungary and in the US simultaneously (they were published in the US less then 30 days after they were first published in Hungary) or which were published in Hungary in accordance with the US formalities (which is extremely unlikely - these include registering the work with the US Copyright Office).
Works first published in a country other than the US before 1923 are public domain in the US.
Works first published in a country other than the US between 1923-1989 are subject to URAA restoration; they are public domain if they were public domain in their country of origin on January 1, 1996. Length of protection in Hungary was 50 years from publication when the author was unknown; this was raised to 70 in 1994, but that was only made retroactive in 1999 (see Article 29 of Act No. VII of 1994 and Article 108 of Act No. LXXVI of 1999). Thus anything that was already PD at 1 July, 1994 (when the law went into effect) in Hungary is PD in the US - specifically, works created by an unknown author and published in Hungary in 1943 or earlier.
To add your language to the list of languages supported by this template, please copy the code of Template:PD-HU-unknown/en (or any other language version you prefer to translate) and replace the text strings in there (the form below can be used to create a translation, the English version is preloaded in the edit box). Please change the parameter lang from en (or whatever language you are translating) to the language code of your language.