1930 called...They want their Postcard back.(edited)
1901 is just a guess, but after a comment by Oh Henry (below) I decided to look a little further instead of guessing. I visited a great site Postcardy and learned that I was about 30 years off. Now, judging by the design on the front - a print on silk with the message embossed in gold - I am going with 1930. They just don't make 'em like this anymore.
Remember the days when neither a zip code or a house number was necessary for a piece of mail to reach its destination? Me neither, but it must have been sweet. Happy New Year.