Reading Chapter 10 Theory & Practice of the Bodhisattva Ideal, Section 7 2nd Para Page 37 of 119 telling that Bodhisattva in the 2nd Ground can be reborn as king in our world system.
Now referring to History of Indian Buddhism Module Unit 11 & 12 The Arising of Mahayana (Chapter 7 The Buddhism of King Asoka), we could see that King Asoka exhibited bodhicitta during the later part of his rein.
Here we see quite similarity between the two. The Gautama went on a schedule trip to see the suffering while Asoka went to war to see the suffering.
King Asoka fulfilled the above equations, so can we said that King Asoka was a Bodhisattva?
Is King Ashoka a Bodhisattva
In my opinion is very difficul to say if king Ashoka was or was not a Bodhisattva . As professor Della Santina says in his writings , Bodhsiattvas have hidden agendas , they can assume any form , it depends on their specific purpose .
So , defining a Bodhisattva from his/her status is not appropriate , it depends more on his/her deeds than social level .
In the case of king Ashosa , at the beginning of his reign he was a pitiless ruler . He caused so much pain and sorrow among his enemies ; but he also did positive things , like spreading Buddhism across Panasia , so thanks to him if the proliferation on the Buddha Teachings was so successful at that time .
King Ashoka
As said Della Santina in his writings about Bodhisattva ideal:
"Now you may ask how we distinguish ordinary Bodhisattvas from Ārya Bodhisattvas.
When does one really become a Bodhisattva? Does one become a Bodhisattva as it is
said in the Bodhicaryāvatāra, and as I told you before that when one merely
formulate to resolve to attain Buddhahood for the benefit of all living beings or it has
to be something more to becomes a Bodhisattva simply than that initial resolve?
Someone or anyone who can see this
intention, formulate his resolve to attain Buddhahood for the benefit of all living
beings, is a Bodhisattva. He is a beginner Bodhisattva; he is an ordinary Bodhisattva.
At that level of the beginner
Bodhisattva, even a vague and indistinct understanding of emptiness is good enough."
What kind of Bodhisattva was Ashoka, an ordinary Bodhisattva or an Arya bodhisattva? It is very difficult to response because there are not accounts enough about this topic.
kings as incarnations
Equating kings with (sort of) gods was quite common occurrence.
In China, Empress Wu Zetian (624-705 CE) lavished praise and favors upon the Buddhist community. Monk Bodhiruci had re-translated a work (Baoyujing, Precious Rain Sutra) as he added that the Empress was the incarnation of the Sun and Moon Light god who had taken flesh to rule China: (wo)men of destiny manufactured on demand as the gods give (expedient) statements of destiny.
The first Emperor of China (III century BCE) -another founder on a warring journey- bestowed upon himself the title of divine ancestor. In pre-Confucian China (divided in various States), rulers were typically seen as wielding power or authority various deities -in perfect Mesopotamian fashion- had entrusted upon them in a sort of cosmic filial relationship (=the Chinese Emperor as Son of Heaven; the Japanese Emperor as descendent of Sun goddess Amaterasu; the King of Nepal as incarnation of Vishnu; Hellenistic monarchs as “god made manifest”; Roman Emperors seen as incarnations of gods, typically Apollo ).
FWIW
Unknowable
In reading Tsong-kha-pa's Great Treatise, paraphrased in the handouts for the course on Lamrim, we are presented with the fact that (at least for an ordinary worldling, a non-Arya), we are incapable of knowing who is or is not a bodhisattva and thus should assume that all are at least possibly bodhisattvas.
Lesson 3: "And if you remember that we, as ordinary beings, cannot recognize a bodhisattva among other people, we must beware of harming anybody as who knows, if he is a bodhisattva, the result
of our wrong action towards him or her will be devastating for us."
As a result, the negative actions of body, speech and mind we could perform toward any individual carry the added risk of being done (unknowingly) to one who is such an unknown bodhisattva.
Lesson 3: "For example, Śraddhā-balādhānāvatāra-mudrā-sūtra states that if someone were to despise any bodhisattva, it would be a sin immeasurably greater than that of someone stealing all the belongings of all the living beings in Jambudvīpa."
Furthermore, if we accept as true that bodhisattvas have the power to take rebirths as they see fit for the benefit of beings, in favorable or unfavorable conditions, it would follow that we should look as carefully at the least among as we do the greatest (Ashoka included).
Regards.