"Of all sad words of tongue or pen, the saddest are these, 'It might have been'." --John Greenleaf Whittier
"The usual label, whether genuine or false, uses the Latin inscription Antonius Stradivarius Cremonensis Faciebat Anno [date]. This inscription indicates the maker (Antonio Stradivari), the town (Cremona), and "made in the year," followed by a date that is either printed or handwritten.
"Copies made after 1891 may also have a country of origin printed in English at the bottom of the label, such as "Made in Czechoslovakia," or simply "Germany." Such identification was required after 1891 by United States regulations on imported goods.
"Thousands upon thousands of violins were made in the 19th century as inexpensive copies of the products of great Italian masters of the 17th and 18th centuries. Affixing a label with the master’s name was not intended to deceive the purchaser but rather to indicate the model around which an instrument was designed. At that time, the purchaser knew he was buying an inexpensive violin and accepted the label as a reference to its derivation. As people rediscover these instruments today, the knowledge of where they came from is lost, and the labels can be misleading."
Source: Encyclopedia Smithsonian
http://www.si.edu/Encyclopedia_SI/nmah/stradv.htm