In 1927 he was part of the Kerry panel that toured the United States and of the Munster team that won the inaugural Railway Cup.
[1] Brosnan's remaining All-Ireland medals were won during Kerry's record-equaling four-in-a-row achievement from 1929 to 1932, being team captain when they defeated Kildare in 1931.
[3] In retirement from playing Brosnan remained closely linked with Kerry football and trained the team to All-Ireland victories in 1939 and 1940.
He participated in a series of engagements during the War of Independence and was among the party that killed District Inspector Tobias O'Sullivan in December 1920.
He resigned his army commission in 1933 when holding the rank of captain, and in the general election of that year unsuccessfully ran as a Cumann na nGaedheal candidate for Kerry.