Complex sentence: The walk-off, strike, and the subsequent handback, were landmark events in the struggle for Aboriginal land rights in Australia--recognition of Indigenous people, their rights and responsibilities for the land, and their ability to practice their law, language and culture.
Split into simpler sentences: The walk-off and strike were landmark events in the struggle for Aboriginal land rights in Australia. For the first time recognition was given of Indigenous people, their rights and responsibilities for the land, and their ability to practise their law, language and culture.