This may refer either 1) to the people whom Solomon called to Jerusalem and who are listed in 8:1 or 2) generally to those who traveled to Jerusalem for the feast, not necessarily to every male person who lived in Israel. (See: [[rc://en/ta/man/jit/figs-hyperbole]])
"Ethanim" is the seventh month of the Hebrew calendar. It is during the last part of September and the first part of October on Western calendars. (See: [[rc://en/ta/man/jit/translate-hebrewmonths]] and [[rc://en/ta/man/jit/translate-ordinal]] and [[rc://en/ta/man/jit/translate-names]])