In the late 1700s, many houses consisted of a
large room with only one chair. Commonly, a long
wide board folded down from the wall, and was used
for dining. The "head of the household" always sat
in the chair while everyone else ate sitting on the
floor Occasionally a guest, who was usually a man,
would be invited to sit in this chair during a meal.
To sit in the chair meant you were important and in
charge. They called the one sitting in the chair the
"chair man." Today in business, we use the
expression or title "Chairman" or "Chairman of the
Board."