Klāvs Siliņš: Latviešu personvārdu vārdnīca. Riga "Zinātne" 1990, ISBN 5-7966-0278-0
Population Register of Latvia: Ārijs was the only given name of 295 persons in Latvia on May 21st 2010.
Etymology
First recorded as a given name of Latvians in the end of the 19th century. Possibly from (biblical) Hebrewאריה(“lion”), from Arius, or a phonetic coinage.