It is read まんじ (manji), and it has a lot of meanings, from kanji origin and from many other cultures in the world.
The origin of this symbol is not certain, but there are traces of it from ancient civilizations in Southeast Europe, Ancient India, and many other places.
Inside a palatial villa in Spain, ancient roman mosaics with this symbol can be found.
Also, there has been discovered the same symbol in the excavations of a Byzantine church in Israel.
Presently it is still widely used in Indian religions (Hinduism, Buddhism and Jainism). From the Sanskrit, “swastika” has two possible translations: “to be good” and “being with higher self”.
In East Asia, the word has taken the meaning of eternity and Buddhism.
Back in the Nazi Germany, when Adolf Hitler rose to power, he took a right-facing and rotated swastika to symbolize the Nazi Party, and later, the state flag of Germany. Nowadays it is a quite outlawed symbol.
In Japan, this symbol can actually be seen very often in temples. The following picture is from a Saisen box (box to put money to offer to the Gods) in Asakusa Temple.
In fact, if we do a little search in Google Maps, we can see that the temples have this symbol identifying them!
It can even be found in a family crest! The following crest if from Hachisuka family.
I find this so much interesting!!!