840
| Ngwagakete: | Ngwagakete 1 |
|---|---|
| Mengwagakgolo: | Ngwagakgolo 8 – Ngwagakgolo 9 – Ngwagakgolo 10 |
| Mengwagasome: | 810s 820s 830s – 840s – 850s 860s 870s |
| Mengwaga: | 837 838 839 – 840 – 841 842 843 |
840 (DCCCXL) ebile ngwagamolele wa go thoma ka Sontaga, ngwaga wa pele ngwagengsome wa 840s, ngwaga wa bomasomenne ngwagengkgolo wa Ngwagakgolo 9, le ngwaga wa bomakgolo seswai masomenne ngwagengkete wa Ngwagakete 1.