During the Edo period (1603 to 1868), criminals in Japan were tattooed by authorities in a practice known as bokkei, making it hard for them to reenter society and find work. This is a primary reason why the tattoo culture of the Yakuza evolved in protest to this branding.
The meaning of Yakuza tattoos are usually related to imagery and symbolism in Japanese art, culture, and religion. The full body suit tattoo, in particular, is a product of Yakuza culture. In the past, it was obligatory in many Yakuza clans for members to get tattoos.
In modern times, the practice is no longer as common. Many Yakuza in the 21st century maintain clean skin to better blend in with society. Conversely, more and more non-Yakuza in Japan are getting tattoos.
Despite these changes, being tattooed is considered a rite of passage for the Yakuza.