SHIMODA CITY, Japan — Navy commanders attended a memorial service Friday for the sailors who lost their lives when the United States attempted to open Japanese ports 150 years ago.

Vice Adm. Robert Williard, the 7th Fleet Commander, and Capt. King Dietrich, the Yokosuka Naval Base commander, were among the dignitaries who visited Gyokusenji Temple, offering wreaths at the graves where the five sailors are buried. Capt. Charles Dixon, the USS Cowpens commander; Capt. Chris Noble, the USS Coronado’s commanding officer; and Lt. Ray Bailey, a Yokosuka chaplain, also attended the ceremony.

The annual memorial service is part of the three-day Black Ship Festival, which began 65 years ago in an effort to promote peaceful relations between the American and Japanese people.

“It is a great honor to participate,” said Dixon, who took part in the service for the second time. “Our heritage is very important.”

The five officers were handed wreaths by girls dressed in kimonos and then walked up to the graves — one by one — to place them and render salutes.

“It is important to continue this very long relationship between the two peoples,” said Noble.

Shimoda City mayor Naoki Ishii, who also participated in the wreath-laying ceremony, agreed.

“I feel the importance of the history and the beginning of the relationship,” he said. “As I watched the service today, I strongly feel the importance of the relationship.”

The service commemorated the five sailors who died when the black ships led by Commodore Matthew Perry landed in Shimoda in 1854. The first was held at the 50th anniversary of his arrival.

This year’s festival also celebrates the signing of the American-Japanese treaty of trade and amity, which opened Japan to the outside world after it had been closed to foreign countries for about 250 years. Perry came to Shimoda demanding that Japan open up to trade and diplomatic relations.

Gyokusenji Temple was home to the first American Consulate in Japan.