In 2015, 48,249 people with foreign citizenship became Swedes, according to figures from Statistics Sweden, and also that year, a new law went into effect requiring all municipalities to host these special ceremonies.
The ceremonies include, for example, speeches, songs and music, and fika, a Swedish tradition of drinking coffee with buns.
The city hall in Nacka, outside of Stockholm, offered a royal touch, with Crown Princess Victoria and Prince Daniel in attendance, while at the ceremony in Botkyrka, Prime Minister Stefan Löfven delivered a speech emphasizing solidarity.
"Stone-throwing and segregation, inequality and injustice shall not characterize our country. We must have strong schools, our country shall be characterized by solidarity," said Löfven.
"It is Sweden's National Day. We express pride in our country and the belief we have in the future," he continued.
Adama Campbell, whose whole family have recently become Swedish citizens, attended the ceremony in Botkyrka and told Swedish Radio News, "I'm doing great! It's very nice."
At that ceremony, new citizens received a certificate, a book, and a little wooden Swedish flag decoration.