Green’s Dictionary of Slang

1. (N.Z.) walking in the mountains with a pack.

c.1864		Tempsky Memoranda (ATLTS) 86: Every man and officer to carry his own swag... Majors were not excluded from the universal infliction of ‘swagging’ [DNZE].
1883		Green High Alps N.Z. 180: Kauffmann gave a significant glance now and then, as he contemplated the packs, but neither he nor Boss ever grumbled, though they knew full well that the heaviest share of the ‘swagging’ must fall to their lot [DNZE].
1898		Transactions N.Z. Institute XXX 415: The packhorses were unloaded on the banks of the Mokoiwi, where the swagging began [DNZE].
1900		J. Scott Colonial Turf 163: Jimmy was a champion growler; long swagging had soured his mind [DNZE].
1916		J. Cowan Bush Explorers (VUWTS) 16: We are off [...] for such another day of marching and swagging [DNZE].
1930		A.D. Dobson Reminiscences 155: When travelling with light camps and swagging, only light utensils could be carried [DNZE].
1958		J.D. Pascoe Great Days in N.Z. Mountaineering 42: Swagging was slower work than walking along with pack-horses [DNZE].

2. (Aus./N.Z.) living as a tramp, esp. in the outback.

1898		Bulletin 20 Aug. Red Page: It’s a tedious job – like swagging.
1911		E.J. Brady River Rovers 45: The rheumatics had got into his right leg, and his swagging days were over.
1927		J. Mathieu Back-block Ballads I: I don’t succumb to swagging, July fogs, or charcoal tarts [AND].
1934		‘E.N. Speer’ Destiny 239: Neville had been initiated into ‘swagging’ and all its wrinkles. He had been shown how to roll ‘fags’, how to make damper, how to boil the billy, how to grill chops in the ashes. Finally, he was taught how to roll the fly and blankets into the swag [AND].

3. see swag v. (1)