So 王 originally meant leader of a tribe, and as the society was developing and growing big, 王 was used to mean King of a kingdom eventually.
王 was later used as a Family Name in China as well.
To confirm our observation, let us examine its evolution history: ( screenshot taken from http://chinese-linguipedia.org )
|Learn one Chinese Character a day - 王|
Now it is time to enjoy a Chinese calligraphy with 王 inside: