did any military use it too?
It was used as an emblem by the Finnish Air Force.
Swastika
The Finnish Air Force used the swastika as an emblem, introduced in 1918, until January 2017. 
where does most of the salt we eat come from Seawater. what is it composed of? Primarily of sodium chloride. what are its health benefits? The sodium present in salt helps nerves and muscles to function correctly, and it is one factor involved in the osmotic regulation of water content in body organs. is it used for religious purposes? Yes, it is used in various religious ceremonies of Hinduism, Jainism, Buddhism and Shintoism. what are the beliefs of the second religion? Jainism is transtheistic and forecasts that the universe evolves without violating the law of substance dualism, auto executed through the middle ground between the principles of parallelism and interactionism. can you mention some of their vows? The "Sallekhana" vow is a ritual to be observed at the end of life. what is their symbol? The swastika, "Om" and the "Ashtamangala". what is the meaning of this first symbol? In Hinduism, the right-facing symbol (卐) is called , symbolizing ('sun'), prosperity and good luck, while the left-facing symbol (卍) is called , symbolizing night or tantric aspects of Kali. what was its use in the early modern europe? A ceiling painted in 1910 in the church of St Laurent in Grenoble has many swastikas.
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Swastika [SEP] Finnish military
The Finnish Air Force used the swastika as an emblem, introduced in 1918, until January 2017. The type of swastika adopted by the air-force was the symbol of luck for the Swedish count Eric von Rosen, who donated one of its earliest aircraft; he later became a prominent figure in the Swedish nazi-movement. The swastika was also used by the women's paramilitary organization Lotta Svärd, which was banned in 1944 in accordance with the Moscow Armistice between Finland and the allied Soviet Union and Britain. The President of Finland is the grand master of the Order of the White Rose.