first hemp seeds arrived in Australia with the First Fleet in 1788.
It turns out that hemp was initially exported to the Australian
colonies to be produced and sold commercially, in great part thanks
to its sturdiness as a fibre and reliability as a raw material.
Commercial hemp production was actually integral to the first
blueprints of the New South Wales colony. Once the settlers arrived,
it wasn’t long before the local population found other uses for the
over 150 years, various governing bodies in Australia encouraged the
propagation of hemp with subsidies and land grants. In this time, the
consumption of cannabis for recreational and medicinal use became
prevalent in both European and Indigenous communities. The Australian
Government saw little need to intervene. This changed in 1925, with
the ratification of the Geneva Convention on Opium and Other Drugs.
As a signatory, Australia was obliged by international agreement to
restrict the use of cannabis to medicinal and scientific purposes.
Ultimately, signatories lumped the drug in with much harder
substances, such as morphine and cocaine.
(Greendorphin: A Brief History of Cannabis in Australia: April 2016
and Medicinal Cannabis Australia: History of Cannabis)