Augustus, who dedicated a temple to the deified Julius (29 B.C.), actually knew the man, so Dorothy King has a point when she writes that if it's good enough for Augustus, it's good enough for her. However, the day of Caesar's birth is not the only part of the Caesar birthday celebration in question. Caesar was born in mid-July in the year 100 B.C. Or was it 101? Or 102? The problem with 100 B.C. is that special dispensations would have had to have been given to allow him to run for various offices if his birth year was 101 or 100. Such permissions had been given before, but evidence about it is missing in Caesar's case. If you're interested in this topic, here's an old article that explains why there is lack of agreement on the topic:
"The Year of Caesar's Birth," by Monroe E. Deutsch. Transactions and Proceedings of the American Philological Association, Vol. 45, (1914), pp. 17-28.For more on how Augustus honored his adoptive father, see
"Julius Caesar in Augustan Rome," by Peter White. Phoenix, Vol. 42, No. 4 (Winter, 1988), pp. 334-356.
When do you think Julius Caesar was born and why?