Shinkichi Tajiri, Universal Paradoxes, page 30: at the bottom of the page it mentions when he started the Ronin series. The commission by the Dutch Ministry of Defence in 1995 lead to the placing of the Sentinel on the Nassauplein (in 1996) in The Hague. Page 38: second column Helen writes about the Ronin of course the pages 34-37 about the Warrior theme lead up to what eventually became the Ronin and the Sentinels. The Sentinels on the bridge over the river Maas by Venlo unveiled in 2007 by Queen Beatrix were the last of the series.
This series of smaller sculptures originally made in Centa Foam and later cast in bronze started in 1995 and one was chosen by the Dutch Ministry of Defence to commemorate the end of the Dutch Draft.