1.5 years. We were engaged after 3 months of "serious dating" (i.e. me letting him break me down. LOL) and were married 4 months after we were engaged. Total time together = 11 of the most amazing months of my life.
Met in April, engages for 4 months, married the following March so total time I knew him before the wedding was 11 months. We've been married 10 years and have a strong marriage.