Kenule Beeson "Ken" Saro-Wiwa (10 October 1941 - 10 November 1995) was a Nigerian writer, television producer, environmental activist, and winner of the Right Livelihood Award and the Goldman Environmental Prize. Saro-Wiwa was a member of the Ogoni people, an ethnic minority in Nigeria whose homeland, Ogoniland, in the Niger Delta has been targeted for crude oil extraction since the 1950s and which has suffered extreme environmental damage from decades of indiscriminate petroleum waste dumping. Initially as spokesperson, and then as president, of the Movement for the Survival of the Ogoni People (MOSOP), Saro-Wiwa led a nonviolent campaign against environmental degradation of the land and waters of Ogoniland by the operations of the multinational petroleum industry, especially the Royal Dutch Shell company. He was also an outspoken critic of the Nigerian government, which he viewed as reluctant to enforce environmental regulations on the foreign petroleum companies operating in the area.

Saro-Wiwa was arrested again and detained by Nigerian authorities in June 1993 but was released after a month. On 21 May 1994 four Ogoni chiefs (all on the conservative side of a schism within MOSOP over strategy) were brutally murdered. Saro-Wiwa had been denied entry to Ogoniland on the day of the murders, but he was arrested and accused of incitement to them. He denied the charges but was imprisoned for over a year before being found guilty and sentenced to death by a specially convened tribunal. The same happened to eight other MOSOP leaders who, along with Saro-Wiwa, became known as the Ogoni Nine.  Some of the defendants' lawyers resigned in protest against the alleged rigging of the trial by the Abacha regime. The resignations left the defendants to their own means against the tribunal, which continued to bring witnesses to testify against Saro-Wiwa and his peers. Many of these supposed witnesses later admitted that they had been bribed by the Nigerian government to support the criminal allegations. At least two witnesses who testified that Saro-Wiwa was involved in the murders of the Ogoni elders later recanted, stating that they had been bribed with money and offers of jobs with Shell to give false testimony, in the presence of Shell's lawyer.  The trial was widely criticised by human rights organisations and, half a year later, Ken Saro-Wiwa received the Right Livelihood Award for his courage, as well as the Goldman Environmental Prize.  On 10 November 1995, Saro-Wiwa and the rest of the Ogoni Nine were killed by hanging by military personnel. They were buried in Port Harcourt Cemetery.  In his 1989 short story "Africa Kills Her Sun", Saro-Wiwa in a resigned, melancholic mood, foreshadowed his own execution.Answer this question using a quote from the following article:

When was he executed?
On 10 November 1995, Saro-Wiwa and the rest of the Ogoni Nine were killed by hanging by military personnel.