The Chinese had touched down in Siam before the Ayutthaya era, but it was not until the second half of the nineteenth century, in 1861, that they arrived in unprecedented numbers when a passenger steamship port in Swatow offered a direct route to Bangkok.
Given those early ties, Phinij Jarusombat, the president of the Thai-Chinese Cultural and Relationship Council, hailed the brotherly Sino-Thai relationship as "the greatest treasure", calling for the two countries to forge even closer ties on all fronts.
Former deputy prime minister Phinij recalled that his ancestor sailed along the Bang Pakong River and settled on the banks of Tha Thua Canal in Chachoengsao during the reign of King Rama IV [1851-1868].
"He came here and married a Thai woman. That is the reason behind the old saying "Thai Jeen Phee Nong Gan" (Thais and Chinese are brothers). I am now the fourth generation," he told the Bangkok Post in an exclusive interview.
His ancestor is one of the Chinese settlers who sailed junks to Siam. Mr Phinij said anecdotes have been passed down for generations. His forebears had come to trade in silk, tea, bowls and other items before they settled on these shores.
Over time, they managed to integrate with Thais until diplomatic relations were established in 1975. This year marks the 45th anniversary of official ties amid the coronavirus outbreak. In July, both leaders continued to affirm that "Thailand and China are family".
Mr Phinij said such long-standing ties account for China's deeper engagement in trade, investment and tourism here than many other countries. In addition, their associations -- whether they be Teochew, Hailam or Hokkien -- abound in Thailand, highlighting strong people-to-people contact.
Reflecting on the course of development, Mr Phinij said the People's Republic of China has risen from a poverty-stricken country to a global superpower since its founding in 1949. When Thais visited their relatives in Swatow, they brought them food and basic necessities. Now that is a thing of the past as it is they who hold feasts for guests.
"I would like to highlight our mutual support during difficult times. For example, we always help each other when we face natural disasters," he said.
Mr Phinij went on to laud Chinese President Xi Jinping's Belt and Road Initiative (BRI), which he described as the revival of the ancient Silk Road founded during the Han Dynasty.
"It is a beacon of hope for the distribution of resources. China is developing a new network of trade routes stretching to the Middle East, South Asia and Europe. It can create jobs and improve people's livelihoods," he said.
In light of this, Mr Phinij called for Thailand to increase cooperation with China, especially in commerce, because its purchasing power is a force to be reckoned with in the global market.
"It has a population of around 1.4 billion. Chinese tourists make up the largest group in Thailand. No matter how many agricultural products we export, we can't meet demand. However, it does not mean that we will overlook other countries, including the US, Australia, Japan and Singapore," he said.
Early this year, the Thailand Development Research Institute said the interconnectedness between the economies of Thailand and China rose more than ten-fold between 1985 and 2013, with bilateral trade, investment and tourism identified as the main beneficiaries (BKP, Sep 20, "Looming giant catches a cold").
When asked whether it shows Thailand's overdependence on China, Mr Phinij dismissed such criticism saying China has never sought territorial control because its policy is not to meddle in any country's internal affairs.
When asked to outline challenges in store, Mr Phinij asked third parties not to interfere in the Sino-Thai relationship especially by spreading what he calls distorted information.
"Do you remember how China was perceived? Under the communist regime, it was portrayed in a negative light, but if that is the case, how can the country with a population of over one billion improve people's livelihoods dramatically? China must be ethical and strong to have made such progress. Western countries often look down on China, but don't forget that it had a glorious past," he said.
In the face of the US-China rivalry, Mr Phinij praised Thailand's friends-to-all stance, but stressed that it must be based on non-interference and fair treatment on all fronts, including the Mekong River.
In April, a study conducted by Eyes on Earth argued China held back water despite higher precipitation, leading to severe droughts in the four Mekong countries downstream. However, China insisted it guaranteed a reasonable discharge of water. To complicate the matter, the US has launched the new Mekong-US Partnership to support development in the region this month.
"I think we should negotiate an agreement on the sharing of resources," he said.
When asked about the South China Sea, which has seen an increasing number of military exercises, both by China and the United States, Mr Phinij commended China for proposing a joint resource development scheme.
"In fact, there is historical evidence that only the Chinese had settled there, but with several countries claiming ownership, it is good that China is putting forward a cooperation scheme. I don't think it will affect our relations unless third parties step in," he said.