If these names sound like your great-grandparents, it's because they haven't been popular since before World War II.
Before anyone saw the Tin Man or the Cowardly Lion on the big screen, Dorothy was a hit. L. Frank Baum's book, "The Wonderful Wizard of Oz," was first published in 1900 and perhaps Baum's Dorothy spawned the popularity of the name.
From 1912-1919, Dorothy, meaning "gift of God," was the third most popular name trailing behind Helen and Mary. From 1920-27, Dorothy ousted Helen, taking second place but by 1935, Dorothy disappeared from the top five for good.
You won't find as many Dorothys today as in the early 20th century, but some famous ones include Dorothy Hamil, the ice skater; Dorothea Dix, a nurse who made great strides in the area of mental illness; and even Nickolodeon's Dora the Explorer (yes, a variation on Dorothy)!
Charles was also popular in the early 20th century. From 1918-29, it held a steady 5th place, but hasn't been in the top five since -- but don't tell the Queen of England!
Charles' origin comes from the German, "free man" and Old English, "manly" so it's no surprise this name befits royalty like the Prince of Wales and Charlemagne, the founder of the Holy Roman Empire. Another famous Charles is Darwin, the father of the theory of evolution. On a lighter note, the nickname, Charlie, gives us the fictional Charlie Brown and actors Chaplin and Sheen -- never boring but not quite the definitions of manly and strong.